Posts Tagged ‘1940s’

Meditations

The luck of Kokura

Friday, August 22nd, 2014

On the morning of August 9th, 1945, a B-29 bomber left the island of Tinian intending to drop an atomic bomb on the city of Kokura, the location of one of the largest arsenals still standing in Japan. On arriving at the target, the plane found it obscured by clouds. It turned south and went to its secondary target: Nagasaki. 

Supposedly, some in Japan still refer to the “luck of Kokura” in reference to this time in which some bad weather saved the lives of tens of thousands of people there. But what really happened that morning? Was it bad weather, or something else, that obscured, and thus saved, Kokura? 

Surprisingly, there are actually a few different theories floating around, and the uncertainty over the matter is generally not realized or acknowledged.

Model of the Kokura arsenal made for targeting purposes, ca. 1945. North is in the lower-right hand corner. Source: USAAF photos, via Fold3.com.

Model of the Kokura arsenal made for targeting purposes, ca. 1945. North is in the lower-right hand corner. Source: USAAF photos, via Fold3.com.

But first, let’s review the basics of the mission. The Kokura/Nagasaki mission (dubbed CENTERBOARD II), as with the Hiroshima mission before it (CENTERBOARD I), did not involve the bomber flying on its lonesome to the target, as is sometimes imagined. There were a total of six planes involved in the mission, all B-29 bombers. One of them was the strike plane that carried the Fat Man implosion bomb (Bockscar).1  Two other planes (The Great Artiste and Big Stink) were instrument and observation planes. One other plane was a “standby” plane (Full House) that was to serve as backup if the three bombing planes ran into air resistance — because they didn’t, it instead flew back to Iwo Jima instead of on to the target after a rendezvous with the bombing plane. Lastly, there were two weather planes that flew out in advance, one to Nagasaki (the Laggin’ Dragon), the other to Kokura (the Enola Gay, the same plane that had dropped the atomic bomb on Hiroshima a few days earlier, but with a different crew). The weather planes would check out bombing conditions and then circle back, helping the bomber plane determine whether the primary or secondary target would be used. Niigata, a third atomic bombing target, was not considered on this mission because of its great geographical distance from Kokura and Nagasaki.

Bockscar was being piloted by Major Charles Sweeney. It had taken off from the island of Tinian at 3:47am, Tinian time. They had arrived at a rendezvous point at Yakushima Island around 9:15am. It rendezvoused with one of the other B-29s (the instrument plane), but did not spot the other one (the photo plane). At 9:50am, the pilot of Bockscar, Charles Sweeney, gave up and continued on to Kokura, having waited some 30 minutes longer than he was supposed to. At 10:44am, they arrived at Kokura. The flight log records that “Target was obscured by heavy ground haze and smoke.” A crew member of Bockscar rated it as “7/10 clouds coverage – Bomb must be dropped visually but I don’t think our chances are very good.”2

Three bombing runs on Kokura were attempted, but “at no time was the aiming point seen,” as the flight log recorded. Visual bombing had been made a mandatory requirement (they did not trust the accuracy of radar-assisted bombing), so this made Kokura a failed mission. Since Bockscar had limited fuel, Sweeney decided to continue on to the secondary target, Nagasaki. They arrived at Nagasaki at 11:50am, which they also found obscured by smoke and clouds, to the degree that they made the target approach entirely by radar. Right at the last possible moment, the clouds parted just enough for the bombardier to site the target and drop the bomb. (It missed the intended target by a significant margin.) Bockscar circled the target once and then, at 12:05pm, took off for Okinawa, and from there, after refueling, Tinian.

Care about the details of the Hiroshima and Nagasaki bombings? Get this book.

Care about the details of the Hiroshima and Nagasaki bombings? Get John’s book. I’m not just saying that because he says nice things about my blog, either.

An aside: For anyone interested in the nitty-gritty details of the Hiroshima and Nagasaki missions, my go-to reference these days is John Coster-Mullen’s Atom Bombs: The Top Secret Insider Story of Little Boy and Fat Man. I first got a copy of John’s book in 2006 or so. John sent me a new copy a few months ago, and I have been impressed with how much new material he has added over the last 8 years. (And I have managed to find a few useful things for him over the years, which have made it into his book as well — duly credited!) If you’re interested in the history of the Manhattan Project, you can’t not have a copy of John’s book… and if your copy is over 5 years old, considered getting an updated edition! All of these little details about times and planes and whatnot come from John’s book.

So what caused the “heavy ground haze and smoke”?

Theory #1: Bad weather

The most common explanation for the obscuring of Kokura is one of weather. It seems to me to be a valid possibility, but let’s pick it apart a bit.

As noted, the Enola Gay had flown ahead to Kokura to scope out the visual conditions. They had radioed back that the visibility was “3/10 low clouds, no intermediate or high clouds, and forecast of improving conditions.”3 That was a favorable-enough weather report that Kokura, the primary target, was chosen as the first run. Upon arriving, however, Bockscar found the weather conditions were now 7/10 — too obscured to bomb. Is this plausible?

Summer weather patterns in Japan, map made in early 1945. Not great for bombing. Source: Produced for the USAAF's IMPACT magazine, high-res version via Fold3.com.

Summer weather patterns in Japan, map made in early 1945. Not great for bombing. Source: Produced for the USAAF’s IMPACT magazine, high-res version via Fold3.com. There is another wonderful map for winter weather as well.

General Groves, in his 1964 memoir, suggests that it might have been the case that the change in weather conditions was simply a matter of how much time had passed between the forecast and arrival of Bockscar. The strike plane was, as noted, delayed by around half an hour. Groves also implies that there may have been a difference between how visual the target was at an angle — how a bombardier sees it — and how it looks from straight above — how a weather plane sees it). He concludes that the reasons for the haze were “never determined.”4

On the face of it, it’s hard to know whether such a rapid change in visibility is possible through entirely natural causes. In some parts of the world, the weather can be very volatile. Japan is one of these parts of the world, especially around the late fall. The variability of Japanese weather conditions was something that the US Army Air Forces knew very well, and was one of the bane of their bombing plans. It was a major issue in the atomic bombing discussions as well since very early on. At the first Target Committee meeting in April 1945, weather was a major point of discussion:

…it was pointed out that the months in which the initial mission will be run constitute the worst weather months of Japan. [...] Dennison pointed out that all weather maps indicated that there were only an average of 6 good bombing days in August and that of those 6 days a conservative estimate would probably result in safely predicting that we would have 3 good days in the month of August but these 3 good days could not be positively predicted in advance of more than 48 hours. 

Elsewhere in the memo it remarks that “3/10ths or less” cloud coverage was considered acceptable for visual bombing. It also notes that “only once in 6 years have there ever been 2 successive good visual bombing days of Tokyo,” which gives some indication of the weather’s variability.

Weather from the nearby city of Shimonoseki for August 8-9, 1945. Click to enlarge, or click here for the Excel file. Source: Japanese M

Weather from the nearby city of Shimonoseki for August 8-9, 1945. Click to enlarge, or click here for the Excel file. Source: Courtesy of the Japanese Meteorological Agency.

So it doesn’t seem impossible that it could have just been according to the weather, though the big difference between the conditions reported by the weather plane and the observed conditions by the strike plane seem, on the face of it, beyond what a half hour’s delay would accomplish. One question I don’t have the answer for is when the weather plane radioed those conditions back. In the case of the Hiroshima run, the weather plane was only 30 minutes earlier than the strike plane. If we assume that was a similar attempt on the second mission, it would mean that the strike plane was reaching the target over an hour after the weather plane had seen it, which could be a significant-enough delay for a serious change in visibility. (And another possibility is that the weather plane could have been, for whatever reason, incorrect — either at the wrong place or had its message garbled.)

There aren’t good weather records from this period, at least none I have seen. The closest site for state weather recording was in Shimonoseki, some 7 miles / 11 km northeast of Kokura. I asked the Japan Meteorological Agency for any records they had from that period and they sent me the above data.5 It is not especially helpful towards answering this question that I can see, but I’m not a meteorologist in the slightest. For me, the big take-away from the data is that it could go from totally clear to totally obscured over the course of an hour, which at least supports the plausibility of the weather theory.

Theory #2: Smoke from firebombing

One of the other causes put forward is that the “smoke and haze” seen over Kokura was actually a result of nearby firebombing. On August 8th, 1945, the 20th AF had sent 221 B-29s to the nearby city of Yahata (Yawata) to drop incendiary bombs.6 Yahata had been bombed several times during the war. It was, in fact, the site of the first B-29 attack on the Japanese homeland in June 1944, and indeed the first bombing attack against the Japanese homeland at all since the Doolittle raid. It had been bombed again in August 1944. The USAAF considered Yahata to be the largest steel producing center in the country, and dubbed it “the Pittsburgh of Japan.” It was the last Japanese city to be hit by a massive B-29 raid, a “night burn job” as a USAAF writer put it, and it was considered “leftover business” that had been scheduled to take place much earlier but delayed because of bad weather.7

Yahata/Yawata target map, March 1945. Kokura arsenal is visible to the east. Source: JapanAirRaids.org. Click here for the uncropped, unadjusted version.

Yahata/Yawata target map, March 1945. Kokura arsenal is visible to the east. Source: JapanAirRaids.org. Click here for the uncropped, unadjusted version.

The weather at Yahata had been 4/10 clouds over the target, but this didn’t matter for B-29 firebombing raids, because accuracy was not as big a concern as with the atomic bombs. The planes had arrived at Yahata around noontime. I’ve found very little in terms of documentation about how much of Yahata was burned out with this raid — perhaps because it was so late in the war, many of the traditional sources for information about incendiary bombing results (especially those contained on the invaluable website JapanAirRaids.org) essentially omit any discussion of this final big raid.

Could the bombing of Yahata have been the cause of the smoke that obscured Kokura? It doesn’t seem impossible, but it seems to me to be somewhat unlikely.

Approximate areas of interest in Yahata and Kokura, as seen on Google Earth today.

Approximate areas of interest in Yahata and Kokura, as seen on Google Earth today.

Bockscar was flying over Kokura just a little under 24 hours after the Yahata raid began. Incendiary raids did produce extreme amounts of smoke cover, as other photographic evidence indicates clearly. Yahata was only around 6 miles / 9 km west of Kokura (and their proximity is emphasized by the fact that both are today just considered wards of a larger city, Kitakyushu).

It seems odd that the Yahata smoke would have caught them off-guard. Wouldn’t the weather plane have noticed that there was smoke over Yahata rolling towards Kokura, or at least threatening it? Yahata is close enough that at the 30,000 feet or so that a weather plane would be flying over Kokura, all they would have to do is glance in its direction to see if there was heavy cloud cover. (One can easily replicate this experience with Google Earth if one chooses.) Could the smoke cloud have been lagged behind by just the amount of time that the weather plane wouldn’t see it, then rush ahead to obscure Kokura an hour later? Could the smoke have gone from non-obscuring to obscuring in just an hour? At the wind speeds measured at Shimonoseki (around 2-12 mph), it doesn’t strike me as super likely, but I’m not an expert in this kind of thing.

Theory #3: Japanese smokescreen

One last, more obscure theory. I first read of this in John Coster-Mullen’s book. I will quote him here:

When [Bockscar] finally arrived at 10:44 AM, smoke and industrial haze had obscured Kokura. Yahata had been firebombed by over 200 of LeMay’s B-29′s the previous day and the smoke had drifted over nearby Kokura. There was also a POW camp right next door to the main downtown power plan. An American prisoner in this camp reported later the Japanese had installed a large pipe that went from the power plant down to the river. He stated that whenever B-29′s were sighted over Kokura, the steam in the plant was diverted through this pipe and into the river. This created enormous condensation clouds that also helped to obscure the city.

John himself seems to have interviewed the POW camp survivor in question, and notes in a footnote that he thinks this was the first time this claim had surfaced in print. I certainly hadn’t seen it anywhere prior to John’s book. John asked Commander Ashworth about this in 1995, and Ashworth replied that this seemed possible, and added “if the Japanese really did that, then they were damn clever!”

German smokescreen use at Wilhelmshaven in June 1943. Caption: "Despite a smoke screen, 168 B-17s of the Eighth Air Force attacked Wilhelmshaven on 11 June. There are three lines of generators to windward of the area covered when the wind is in the north, as it was in this case. Generator boats are at the upper left. Despite the extent of the smoke screen hits are observed inside the circle..." Source: USAAAF IMPACT magazine, vol. 1, No. 5, August 1945, page 18.

German smokescreen use at Wilhelmshaven in June 1943. Caption: “Despite a smoke screen, 168 B-17s of the Eighth Air Force attacked Wilhelmshaven on 11 June. There are three lines of generators to windward of the area covered when the wind is in the north, as it was in this case. Generator boats are at the upper left. Despite the extent of the smoke screen hits are observed inside the circle…” Source: USAAAF IMPACT magazine, vol. 1, No. 5, August 1943, page 18.

A few weeks ago, there was a story carried by Japanese newspapers along these lines:

As the 69th anniversary of the Nagasaki atomic bombing approaches, a former mill worker in the present-day city of Kitakyushu, Fukuoka Prefecture, spoke about his untold story on how he burned coal tar to block the view of U.S. aircraft as they were about to drop the A-bomb on the city. … Of the three workers, Oita resident Satoru Miyashiro, 85, who worked at a can factory in the steel mill at around the end of the war said he burned coal tar to lay a smoke screen on Aug. 9, 1945. … Miyashiro said about two days before the Nagasaki attack Yawata steel workers learned that Hiroshima had been wiped out by the “new bomb” from their colleagues who had come back to Yawata via Hiroshima. He thought the next target would be his city as there were arms factories located in the area.

Note that this isn’t quite the same thing — this is someone in Yahata who was burning coal tar after hearing an air raid drill, and the smoke going downwind (east) to Kokura. I find it a little odd that the worker in question doesn’t mention that Yahata itself was firebombed less than a day before he decided to do this.

Are either of these theories plausible? In terms of, could they have done these things — of course. Turning on an incinerator is not an implausible action, and neither is the steam cloud scenario.

But would this have reduced the visibility over Kokura from 3/10 to 7/10 in the time it took the strike plane to get there? I’m not an atmospheric scientist, so I wouldn’t want to hazard a strong position on this. One can presumably model both of these scenarios and see if either were possible. I would be extremely interested if anyone wanted to that!

Susquehanna Steam Electric Station — just an example of what a very large nuclear power plant can generate in terms of steam. It's a lot of steam. Could it obscure a city downwind of it from a B-29 bomber? Image source.

Susquehanna Steam Electric Station — just an example of what a very large nuclear power plant can generate in terms of steam. It’s a lot of steam. Could it obscure a city downwind of it from a B-29 bomber? Image source.

My gut thought is that they were not super likely to be wholly responsible for the cloud cover. If it had been steam from a single plant, I suspect someone on Bockscar would have noted it as such. We have lots of experience with steam-generating power plants — think of the clouds created by nuclear cooling towers. They certainly can put out a lot of steam. Would it be enough to block off the entire city? I’m kind of dubious.

What about the coal tar possibility? I’m especially dubious that this would have been enough. Setting up honest-to-god smokescreen for an entire city is hard work, even if you are a professional. When the Germans wanted to protect individual places (like plants) from bombers they set up dozens to hundreds of smoke pots to do the job, or used multiple dedicated smoke generators. Some of the larger smokescreen images I have found clearly involve lots of smoke sources placed at good intervals upwind of the target they are meant to protect. So I don’t know.

On the other hand, if the smoke from Yahata was not from the firebombing but instead something deliberate, it would explain the time delay issue. If the wind was going due east at around 5 mph, that would in fact be perfect for putting a smoke cover over Kokura. So it has its merits as a theory.

Conclusion

There are narrative aspects of each theory that appeal, and each of them change what is meant by the “luck of Kokura.” If bad weather is what saved Kokura, then it becomes a metaphor for how serendipitously life and death are dealt out by the hands of fate. If it was smoke from the firebombing of Yahata, then it becomes an ironic story about the Army Air Forces’ zeal for destruction could become counterproductive. If it was the result of deliberate action on behalf of the Japanese, then it becomes something much more complicated, a story about how individual action may have led to the saving of some lives… and the dooming of others. It also would change the standard story of how defenseless the Japanese were against these weapons.

The bombing of Nagasaki. Original source. Slightly edited to improve foreground/background distinction.

Of course, what was lucky for Kokura was not so for Nagasaki.

Looking at these three options, I find the weather theory the easiest one to stomach. Japanese weather patterns were notoriously hard to predict and it was known as the worst season for bombing conditions. That they could change over an hour seems unsurprising to me, especially for a coastal city, where clouds can come and go which impressive rapidity (as someone who has lived in the Berkeley, Boston, and New York areas can attest). I like the irony of the Yahata story, but there are things that just don’t add up — I don’t see why the weather plane would not have mentioned it, and it seems implausible to me that it would take almost exactly 24 hours for the heavy cloud cover to have migrated a mere 5-10 miles. And for reasons indicated, I’m not sure I buy the smokescreen story — it would have been really difficult to pull off that degree of cloud cover reliably. It would have taken tremendous foresight and luck. And it is strange that this story would be “buried” for so long. This doesn’t mean that someone didn’t try it (I am emphatically not calling anyone a liar!). It just means that I’m not sure it would have worked even if they did try it.

A separate possibility is “all of the above.” Maybe the weather was bad. Maybe there was haze from the Yahata bombing. Maybe someone did try to release steam or smokescreen. Maybe all of these things occurred at once, making “the luck of Kokura” something that was the result of multiple causes. That would make Kokura extra lucky, I suppose, and not fit into any of the above pat narratives. And make Nagasaki extra un-lucky in turn.

In the end, it doesn’t really matter which of these things happened. The bare fact is that Kokura didn’t get bombed and Nagasaki did. But I find looking into these kinds of questions useful as a historian. Too often it is easy to take for granted that the explanations given in narrative works of history are “settled,” when really they are often resting on very thin evidence, thinner perhaps than the historian who writes them realizes. I don’t think we really know what happened at Kokura, and I’m not sure we ever truly will.

Notes
  1. Sometimes you see it as “Bock’s Car,” but it said “Bockscar” on the side of the B-29. This is one of those places where I say, “who cares?” but purists are concerned with this kind of detail. []
  2. Flight diary of Lt. Fred Olivi, quoted in Coster-Mullen’s book. []
  3. Bockscar flight log by Commander Frederick Ashworth, included in Norman F. Ramsey, “History of Project A,” (27 September 1945). A full of copy of Ramsey’s report is included in Coster-Mullen’s Atom Bombs book. []
  4. Leslie Groves, Now it Can Be Told, 345: “At Kokura, they found that visual bombing was not possible, although the weather plane had reported that it should be. Whether this unexpected condition was due to the time lag, or to the difference between an observer looking straight down and a bombardier looking at the target on a slant, was never determined.” []
  5. Here is the original Excel file they sent me. []
  6. Most US sources list the city as “Yawata,” but it apparently corresponds with what is today transliterated as the city of Yahata, in Fukoka prefecture, and there is an entirely different city known as Yawata in Kyoto Prefecture. The kanji is the same. Yahata has since been absorbed by Kitakyushu, along with Kokura. []
  7. Tom Prideaux, “Mission to Yawata, 7 Aug. 1945,” IMPACT, vol. 3, no. 9 (September-October 1945), 53. []
Redactions

The Kyoto misconception

Friday, August 8th, 2014

This week we talk again of the anniversaries of the atomic bombings of Hiroshima and Nagasaki. But if the military brass had its way in 1945, we would speak of Kyoto as well. Kyoto was spared because of a personal intervention: the US Secretary of War, Henry L. Stimson, did not think it should be bombed. This story has been told many times, often as an example of how thin a line there is between life and death, mercy and destruction. But there’s an angle to this story that I think has gone overlooked: how the debate about targeting Kyoto led President Truman to a crucial misunderstanding about the nature of the atomic bomb.

Toji pagoda, in Kyoto, today. Had the Little Boy bomb been dropped on Kyoto, it would have likely been destroyed, as it was less than 3,000 feet from the proposed "Ground Zero" point. Source: Wikimedia Commons.

Toji pagoda, in Kyoto, today. Had the Little Boy bomb been dropped on Kyoto, it would have likely been destroyed, as it was less than 3,000 feet from the proposed “Ground Zero” point. Source: Wikimedia Commons.

Let’s start from the beginning. The first concrete discussions about what cities to target with the atomic bomb did not take place until the spring of 1945. On April 27, 1945, the first “Target Committee” meeting was held in the Pentagon. General Leslie Groves, head of the Manhattan Project, was there at the beginning of the meeting, as was Brig. General Lauris Norstad of the US Army Air Forces. But the meeting was mostly presided over by Groves’ deputy, Brig. General Thomas Farrell. Among the scientists in attendance were John von Neumann and William Penney (but not Oppenheimer).

The basic decisions made at this meeting were regarding operational aspects of the bombing. The use of the atomic bomb would have to be done with visual targeting, not by use of radar. The weather had to be good — no easy thing to predict for Japan in the late summer. The targets should be “large urban areas of not less than 3 miles in diameter existing in the larger populated areas… between the Japanese cities of Tokyo and Nagasaki… [and] should have high strategic value.” A list of possible targets that met this criteria was given: Tokyo Bay, Kawasaki, Yokohama, Nagoya, Osaka, Kobe, Kyoto, Hiroshima, Kure, Yawata, Kokura, Shimosenka, Yamaguchi, Kumamoto, Fukuoka, Nagasaki, Sasebo. Of these, Hiroshima was noted as “the largest untouched target not on the 21st Bomber Command priority list.” Tokyo, on the other hand, was “now practically all bombed and burned out and is practically rubble with only the palace grounds left standing.” It was further noted that they had to take into account that the policy of the 20th Air Force was now “systematically bombing out” cities “with the prime purpose in mind of not leaving one stone lying on the other,” and that they would not likely reserve targets just for the Manhattan Project.1

1945-04-28 - Nordstad - Target Information

This list of targets was forwarded on the next day and someone — probably Groves — indicated that Hiroshima was target #1, Kyoto target #2, Yokohama target #3,  and that other targets of high interest included Tokyo Bay, Fukuoka, Nagasaki, and Sasebo.2 Why Kyoto? A target data sheet, compiled on July 2nd, gives some indication of its perceived strategic value. Kyoto, according to this summary, was a major rail connection between Osaka and Tokyo, had several major factories inside of it (producing “ordnance and aircraft parts” as well as “radio fire control and gun direction equipment”), and numerous “peace time factories [that] have been converted to war purposes.” It also had a new aircraft engine factory that could turn out an estimated 400 engines a month, which would make it the second largest such factory in Japan.3 It had a population of over a million people, of which a “sizeable proportion” of the workers commuted to war production plants. “Many people and industries are being moved here as other cities as destroyed,” another datasheet noted. Its construction was “typical Jap city” — lots of wooden residential houses, and thus very flammable.4

At the Second Meeting of the Target Committee, Kyoto increased in perceived importance. This meeting was held in J. Robert Oppenheimer’s office at Los Alamos on May 10-11, 1945, and was dominated by scientists in attendance. Along with discussing the ideal burst altitude of the bomb, calculated to destroy the largest amount of “light” buildings (e.g. housing), the scientists also discussed targets. At this point, the target list was #1 Kyoto, #2 Hiroshima, #3 Yokohama, #4 Kokura, and #5 Niigata. Aside from the aforementioned justifications (population size, industries), the committee report noted that:

From the psychological point of view there is the advantage that Kyoto is an intellectual center for Japan and the people there are more apt to appreciate the significant of such a weapon as the gadget. … Kyoto has the advantage of the people being more highly intelligent and hence better able to appreciate the significance of the weapon.5

No surprise, perhaps, that the scientists would believe that there was strategic value in making sure that other intellectuals saw the effects of the atomic bomb.

Target map of Kyoto, June 1945, with atomic bomb aiming point indicated. This image is a composite of eight separate microfilm images from two maps (Kyoto North and Kyoto South) that I stitched together in Photoshop.

Target map of Kyoto, June 1945, with atomic bomb aiming point indicated. This image is a composite of eight separate microfilm images from two maps (Kyoto North and Kyoto South) that I stitched together in Photoshop. If you want the full uncropped version (7MB), you can get it here.

The plans to bomb Kyoto were serious enough to warrant the creation of a target map, showing the city with a 1.5 mile circle drawn around a starred aiming point — the roundhouse of the railway yards. Even today this is an easy target to find, visually, using Google Maps — it is the site of the Umekoji Steam Locomotive Museum today. One suspects that if Kyoto had been atomic bombed this site would have the same iconic status as the Genbaku Dome/Hiroshima Peace Memorial today.6

On May 15, 1945, a directive was issued to the US Army Air Forces requesting that Hiroshima, Kyoto, and Niigata be put on a list of “Reserved Areas” not to be bombed, so that they could be preserved as atomic bombing targets. Why Yokohama and Kokura was not put on the list as well at that time is not known to me, but presumably Yokohama was known to be a planned target, as it was ruinously firebombed on May 29th. (As an aside, the mushroom cloud from atomic bombing of Yokohama would probably have been visible from the Imperial Palace in Tokyo, according to NUKEMAP3D.) Kokura was added to the “reserved” list on June 27.7

On May 30th, Groves had a morning meeting with Stimson to discuss the targeting decisions. In Groves’ later recollections, Stimson told Groves that on the matter of the bomb targeting, Stimson was “the kingpin” and that nobody else would overrule him. When Groves told him of the targeted cities, Stimson (again, in Groves’ later recollection), told him bluntly: “I don’t want Kyoto bombed.” Groves recalled Stimson telling him that Kyoto was a cultural center of Japan, the former capital of the country, “and a great many reasons” more why he didn’t want it bombed.8 Stimson had been having numerous meetings about the atomic bomb and the firebombing of Tokyo over these days — and was resistant to the new mass bombing tactics. On June 1, Stimson recorded in his diary a discussion he had with the commander of the US Army Air Forces, about the fact that the US policy was now one of mass destruction:

Then I had in General Arnold and discussed with him the bombing of the B-29′s in Japan. I told him of my promise from Lovett that there would be only precision bombing in Japan and that the press yesterday had indicated a bombing of Tokyo which was very far from that. I wanted to know what the facts were. He told me that the Air Force was up against the difficult situation arising out of the fact that Japan, unlike Germany, had not concentrated her industries and that on the contrary they were scattered out and were small and closely connected in site with the houses of their employees; that thus it was practically impossible to destroy the war output of Japan without doing more damage to civilians connected with the output than in Europe. He told me, however, that they were trying to keep it down as far as possible. I told him there was one city that they must not bomb without my permission and that was Kyoto.

Stimson went to President Truman with his concerns a few days later, on June 6th. His diary records the following exchange:

I told him I was anxious about this feature of the war for two reasons: first, because I did not want to have the United States get the reputation of outdoing Hitler in atrocities; and second, I was a little fearful that before we could get ready the Air Force might have Japan so thoroughly bombed out that the new weapon would not have a fair background to show its strength. He laughed and said he understood. Owing to the shortness of time I did not get through any further matters on my agenda.

What was Truman laughing at? If Truman was a clever man, one might guess that it was the apparent contradiction between not wanting to “outdo Hitler in atrocities” but also wanting to make sure there was enough of Japan left to destroy to make an impression when the atomic bomb was ready. But Truman was not known as a clever man — he probably just thought it was amusing that we were becoming so successful at destroying Japan that we’d need to preserve a little more to destroy later.

Groves had not given up on targeting Kyoto, however. He repeatedly attempted to see if Stimson would budge. Kyoto was a rich target — more important than many of the others on the list. Why did Stimson insist on sparing Kyoto? The answer you find on the Internet is straightforward but a little glib: in the late 1920s, Stimson had been Governor-General to the Philippines, and had visited the city and loved it (and had perhaps been there on his honeymoon). Thus there was a personal connection. This is not present in most of the books on the bomb decision, oddly enough — the fact that Stimson opposed bombing Kyoto is mentioned, but other than noting it was a cultural capital, it is not probed much deeper. The historiography on Stimson’s decision is one about the moral underpinnings of it: Was Stimson trying to assuage guilt? Was he trying to preserve better postwar relations with the Japanese? There are competing interpretations, and not a lot of evidence to work from.9

Truman and Stimson, August 1945. Source: George Skadding, LIFE Magazine.

Truman and Stimson, August 1945. Source: George Skadding, LIFE Magazine.

Which brings us, at last, to what interests me the most here. I am not so interested in why Stimson spared Kyoto, or how scholars have interpreted that. What I am interested in is this: Stimson’s attempt to keep Kyoto off the target list for the atomic bomb went to the very top. The list of targets was not finalized until July 25th, 1945, when Stimson and Truman were both at the Potsdam Conference. There, Stimson told Truman for a final time why Kyoto had to be kept off. From Stimson’s diary entry from July 24th:

“We had a few words more about the S-1 program, and I again gave him my reasons for eliminating one of the proposed targets [Kyoto]. He again reiterated with the utmost emphasis his own concurring belief on that subject, and he was particularly emphatic in agreeing with my suggestion that if elimination was not done, the bitterness which would be caused by such a wanton act might make it impossible during the long post-war period to reconcile the Japanese to us in that area rather than to the Russians. It might thus, I pointed out, be the means of preventing what our policy demanded, namely a sympathetic Japan to the United States in case there should be any aggression by Russia in Manchuria.”

Stimson left the meeting thinking Truman completely understood the matter, and the final target order — with Hiroshima, Kokura, Niigata, and Nagasaki (the latter added only then) — was sent out.

But what did Truman take away from this meeting? We can look at Truman’s own diary entry from July 25th:

This weapon is to be used against Japan between now and August 10th. I have told the Sec. of War, Mr. Stimson, to use it so that military objectives and soldiers and sailors are the target and not women and children. Even if the Japs are savages, ruthless, merciless and fanatic, we as the leader of the world for the common welfare cannot drop that terrible bomb on the old capital or the new.

He and I are in accord. The target will be a purely military one and we will issue a warning statement asking the Japs to surrender and save lives. I’m sure they will not do that, but we will have given them the chance. It is certainly a good thing for the world that Hitler’s crowd or Stalin’s did not discover this atomic bomb. It seems to be the most terrible thing ever discovered, but it can be made the most useful. 

This passage reflects an incredible misconception. Truman appears, here, to believe that Hiroshima was “a purely military” target, and that “soldiers and sailors” would be killed, “not women and children.” But of course every city on that list was inhabited primarily by civilians. And by the calculus of war being waged, every city on that list had a military connection — they produced weapons for the military.

This is not to say that there isn’t a distinction between the targets, just that it is slighter than Truman’s diary entry suggests. Stimson was probably trying to say that the cultural value of Kyoto outweighed its value as a strategic target. Stimson was no doubt aware that Kyoto had war industries inside of it, but thought these were worth overlooking. The lack of a large military base in Kyoto made it more of a “civilian” target in his mind than Hiroshima or Nagasaki. But Truman seems to have come away from this discussion with the understanding that it was a stark contrast between a “civilian” target and a “military” one. As J. Samuel Walker has noted, if Hiroshima had been a more important military target, it likely would have already been bombed much earlier — the fact that it was still intact was in part a reflection of its lack of military presence.10

Statistics on "casualties among school children" at Hiroshima, from Medical Effects of Atomic Bombs, volume VI (July 1951).

Statistics on “casualties among school children” at Hiroshima, from Medical Effects of Atomic Bombs, volume VI (July 1951), page 25.

Am I reading too much into one diary entry? I don’t think so. Consider that after the second bomb was dropped, Truman issued a “stop” order on further atomic bombing, telling Secretary of Commerce (and former VP) Henry Wallace that “the thought of wiping out another 100,000 people was too horrible. He didn’t like the idea of killing, as he said, ‘all those kids.’”11 Because both of those atomic bombs did kill a lot of civilians, and a lot of children in particular. In fact, as a postwar report explained, elementary schools were seen as a great data source on the mortality of the bombs because good records were kept “of the fate of the children.” So you get really gristly statistics about the percentage of schoolchildren killed at various distances from Ground Zero — something that really underscores that these “purely military” targets were a little less than “pure.” Sometimes these passages have been taken to argue that Truman really did wrestle with the moral issues, but I think they show something else: that he did not understand them until after the fact.12

As another bit of evidence along these lines, consider what Truman wrote to Senator Richard Russell on August 9th, before he received a detailed report of the damage at Hiroshima:

I know that Japan is a terribly cruel and uncivilized nation in warfare but I can’t bring myself to believe that, because they are beasts, we should ourselves act in the same manner.

For myself, I certainly regret the necessity of wiping out whole populations because of the ‘pigheadedness’ of the leaders of a nation and, for your information, I am not going to do it until it is absolutely necessary…

My object is to save as many American lives as possible but I also have a humane feeling for the women and children in Japan.

Does this look like a man who understands that he signed off an an order that was being used to obliterate Japanese elementary schools, or someone who really still believes that they are primarily destroying “military” targets exclusively?13

I think Truman came away from the discussions about Kyoto with a very incorrect understanding of what the atomic bomb targets were. I think he really, genuinely did not understand the degree to which civilians would compose the vast bulk of the casualties. How could he misunderstand this point? Because of the framing of the discussion, perhaps — Stimson really wanted him to agree with him that Kyoto was somehow a different category of target. Perhaps this is the greatest legacy of the Kyoto decision: it created what looked like a great moral distinction regarding the bomb, one which Truman thought he had taken a decisive stance on. But in the end it confused Truman as to the possible moral options (he was never presented with the question of whether a “demonstration” should be made, for example, or whether Japan should be given a direct warning first), and he chose one apparently under false pretenses.

I don’t think Stimson attempted to purposely mislead Truman, though. Rather, I think the root of Truman’s misunderstanding was that he was a very incurious man when it came to nuclear matters. He liked the idea of the bomb as a source of political power, but he didn’t really get into the details of how it was made or used, not in the way Roosevelt did, and not in the way Eisenhower would. He rarely questioned his advisors, rarely analyzed the issues with independent judgment, and he never grappled with the big ideas. There are many other examples of this from later in his Presidency as well. Despite having his name forever linked to the atomic bomb, one does not get the impression from even his own retrospective, self-justifying accounts that he really took the issues seriously, or even fully understood them. As a result of his lack of interest, and lack of attention, he never thought to ask how many civilians would die at Hiroshima — it doesn’t appear to him to have even been a consideration until after the damage was done.

Notes
  1. Notes on the Initial Meeting of the Target Committee [held on 27 April 1945]” (2 May 1945), in Correspondence (“Top Secret”) of the Manhattan Engineer District, 1942-1946, microfilm publication M1109 (Washington, D.C.: National Archives and Records Administration, 1980), Roll 1, Target 6, Folder 5D, “Selection of Targets.” []
  2. Lauris Norstad to Director, Joint Target Group, “Target Information” (28 April 1945), in Correspondence (“Top Secret”) of the Manhattan Engineer District, 1942-1946, microfilm publication M1109 (Washington, D.C.: National Archives and Records Administration, 1980), Roll 1, Target 6, Folder 5D, “Selection of Targets.” []
  3. Kyoto,” (2 July 1945), in Correspondence (“Top Secret”) of the Manhattan Engineer District, 1942-1946, microfilm publication M1109 (Washington, D.C.: National Archives and Records Administration, 1980), Roll 1, Target 6, Folder 5D, “Selection of Targets.” []
  4. Files from an envelope labeled “New Dope on Cities,” (14 June 1945, but with some files dated later), in Correspondence (“Top Secret”) of the Manhattan Engineer District, 1942-1946, microfilm publication M1109 (Washington, D.C.: National Archives and Records Administration, 1980), Roll 3, Target 8, Folder 25, “Documents Removed From Groves’ Locked Box.” []
  5. J.A. Derry and N.F. Ramsey to L.R. Groves, “Summary of Target Committee Meetings on 10 and 11 May 1945,” in Correspondence (“Top Secret”) of the Manhattan Engineer District, 1942-1946, microfilm publication M1109 (Washington, D.C.: National Archives and Records Administration, 1980), Roll 1, Target 6, Folder 5D, “Selection of Targets.” []
  6. The map is found in an envelope labeled “Pictures,” dated 15 June 1945, in Correspondence (“Top Secret”) of the Manhattan Engineer District, 1942-1946, microfilm publication M1109 (Washington, D.C.: National Archives and Records Administration, 1980), Roll 3, Target 8, Folder 25, “Documents Removed From Groves’ Locked Box.” There was also a map of Niigata and aerial photos of Kokura and Kyoto in the envelope. []
  7. Reserved Areas” (27 June 1945), in Correspondence (“Top Secret”) of the Manhattan Engineer District, 1942-1946, microfilm publication M1109 (Washington, D.C.: National Archives and Records Administration, 1980), Roll 3, Target 8, Folder 25, “Documents Removed From Groves’ Locked Box.” []
  8. Quoted in Richard Rhodes, The Making of the Atomic Bomb (Simon and Schuster, 1986), on 640-641. []
  9. See Jason M. Kelly, “Why Did Henry Stimson Spare Kyoto from the Bomb?: Confusion in Postwar Historiography,” Journal of American-East Asian Relations 19 (2012), 183-203, and Sean Malloy, “Four Days in May: Henry L. Stimson and the Decision to Use the Atomic Bomb,” The Asia Pacific Journal, Vol. 14-2-09, April 4, 2009. []
  10. J. Samuel Walker, Prompt and Utter Destruction: Truman and the Use of Atomic Bombs Against Japan (University of North Carolina Press, 2004), 61-62. Walker is one of the few authors I’ve seen who have pointed out the discrepancy in Truman’s understanding. I also appreciate that his book title properly refers to the use of “atomic bombs” (plural) as opposed to “the atomic bomb.” []
  11. From Wallace’s diary, quoted in Walker, page 86. []
  12. Bart Bernstein wrote an article in the late 1990s which discusses, among other things, the unreliability of Truman’s after-the-fact narratives about his feelings about this, including one completely false document that claims that Truman decided on Hiroshima and Nagasaki himself! The falseness of this is obvious to anyone who knows even a bit about this history, since Nagasaki was not the primary target for the August 9th run, but the secondary. See Barton J. Bernstein, “Truman and the A-Bomb: Targeting Noncombatants, Using the Bomb, and His Defending the ‘Decision’,” The Journal of Military History 62, no. 3 (July 1998), 547-570. []
  13. Truman’s public statements and press releases, as an aside, need to be carefully scrutinized before being taken as evidence of Truman’s point of view, since he did not write many of them. []
Meditations

A bomb without Einstein?

Friday, June 27th, 2014

If Albert Einstein had never been born, would it have changed when nuclear weapons were first produced? For whatever reason, I’ve seen this question being asked repeatedly on Internet forums, as odd as it is. It’s kind of a silly question. You can’t go in and tweak one variable in the past and then think you could know what the outcome would be. History is a chaotic system; start removing variables, who knows what would happen. Much less a variable named Albert Einstein, one of the most influential physicists of the 20th century, and whose importance extended well past the equations he wrote… and those were pretty important equations, at that!

1946 - Einstein Time magazine - detail

Einstein’s 1946 cover of Time magazine. The mushroom cloud is a beautifully executed combination of the Trinity and Nagasaki mushroom clouds.

On the other hand, this kind of science-fiction counterfactual can have its usefulness as a thought experiment. It isn’t history, but it can be used to illustrate some important aspects about the early history of the atomic bomb that a lot of people don’t know, and to undo a little bit of the “great man” obsession with bomb history. Albert Einstein has been associated with the bomb both through his famous mass-energy equivalence calculation (E=mc²) and because of the famous Einstein-Szilard letter to Roosevelt in 1939. On the face of it, this gives him quite a primary role, and indeed, he usually shows up pretty quickly at the beginning of most histories of the Manhattan Project. But neither E=mc² nor the Einstein-Szilard letter were as central to the Manhattan Project’s success as people realize — either scientifically or historically.

In terms of the science, E=mc² gets a lion’s share of attention, most perfectly expressed by Einstein’s portrait on the cover of Time magazine in 1946 (above) with his equation emblazoned on a mushroom cloud. A lot of people seem to think that E=mc² played a key role in the development of the bomb, that the weapon just falls out of the physics. This is wrong. The equation can help one understand why atomic bombs work, but it doesn’t really tell you how they work, or whether you would expect them to even be possible.

The way I like to put it is this: E=mc² tells you about as much about an atomic bomb as Newton’s laws do about ballistic missiles. At some very “low level” the physics is crucial to making sense of the technology, but the technology does not just “fall out” of the physics in any straightforward way, and neither of those equations tell you whether the technology is possible. E=mc² tells you that on some very deep level, energy and mass are equivalent, and the amount of energy that mass is equivalent is gigantic. But it says nothing about the mechanism of converting mass into energy, either whether one exists in the first place, or whether it can be scaled up to industrial or military scales. It gives no hints as to even where to look for such energy releases. After the fact, once you know about nuclear fission and can measure mass defects and things like that, it helps you explain very concisely where the tremendous amounts of energy come from, but it gives you no starting indications.

Eddington's famous plate of the 1919 solar eclipse, which helped confirm Einstein's theory of General Relativity. Very cool looking, and interesting science. But not relevant to atomic bombs. Source.

Eddington’s famous plate of the 1919 solar eclipse, which helped confirm Einstein’s theory of General Relativity. Very cool looking, and interesting science. But not relevant to atomic bombs. Source.

What about the rest of Einstein’s main theoretical work, both Special and General Relativity Theory? They are pretty irrelevant to bomb-making. The physical processes that take place inside atomic bombs are what physicists call “non-relativistic.” Relativity theory generally only shows its hand when you are talking about great speeds (e.g. large fractions of the speed of light) or great masses (e.g. gravitational fields), and neither of those come into play with fission bombs. You can neglect relativity when doing the math to make a bomb.1

An intelligent follow-up question might be: “well, just because relativity theory didn’t play a role in the bomb process itself doesn’t answer the question of whether it started physics on a path that led to the bomb, does it?” Without getting into a long timeline of the “science that led to the bomb,” here, I think we could reasonably summarize the situation like this: Einstein’s 1905 papers (of which E=mc² was one) did indeed play a role in the subsequent developments that followed, but perhaps not as direct a one as people think. E=mc² didn’t inspire physicists to start looking into processes that converted mass to energy — they were already looking into those through an entirely separate (and earlier) line of development, namely the science of radioactivity and particle physics. The fact that huge amounts of energy were released through nuclear reactions, for example, had already been studied closely by the Curies, by Ernest Rutherford, and by Frederick Soddy prior (but only just) to 1905.

Arguably, the most important work Einstein did in this respect was his work on the photoelectric effect (for which he was awarded the Nobel Prize in Physics for 1921), which helped establish the physical reality of Max Planck’s idea of a quantum of energy, which helped kick off investigations into quantum theory in earnest. This had a big influence on the later direction of physics, even if Einstein himself was never quite comfortable with the quantum mechanics that developed in subsequent decades.

The Hahn-Meitner-Strassman experiment apparatus, at the Deutsches Museum in Munich. My own photo.

The Hahn-Meitner-Strassman experiment apparatus, at the Deutsches Museum in Munich. My own photo.

Did any of the relativity work lead, though, down the path that eventually arrived at the discovery of fission in 1939? I don’t think so. The experiments that Hahn, Meitner, and Strassman were doing in Berlin that lead to the discovery of fission in uranium were themselves careful replications of work that Fermi had done around 1934. Fermi’s work came directly out of an experimentalist, nuclear physics context where physicists were bombarding substances with all manner of subatomic particles to see what happened. It was most directly influenced by the discovery of the neutron as a new sub-atomic particle by Chadwick in 1932. This came out of work on atomic theory and atomic modeling that was being done by Rutherford and his students from the early 1910s-1920s. And this early nuclear physics came, most directly, out of the aforementioned context of radioactivity and experimental physics of the late 19th century.

None of which has a strong, direct connection to or from Einstein’s work in my mind. They have some overlaps of interest (e.g. Bohr was a student of Rutherford’s), but the communities working on these sorts of experimental problems are not quite the same as the more theoretical circle that Einstein himself worked in.2 If we somehow, magically, removed Einstein’s early work from the equation here, does the output change much? There would be some reshuffling, probably, but I sort of think that Rutherford would still be doing his thing anyway, and from that much of the other work that led to the bomb would eventually come out, even if it had a somewhat different flavor or slightly different timeline.

My least favorite way of depicting the fission process, where energy (E) is a magic lightning bolt coming out of the splitting atom. In reality, most of the energy comes in the form of the two fission products (F.P. here) repelling from each other with great violence. Source.

This is my least-favorite way of depicting the fission process, where energy (E) is a magic lightning bolt coming out of the splitting atom. In reality, most of the energy comes in the form of the two fission products (F.P. here) repelling from each other with great violence. Source.

Do you even need to know that E=mc² to make an atomic bomb? Perhaps surprisingly, you don’t! There are other, more physically intuitive ways to calculate (or measure) the energy release from a fission reaction. If you treat the fission process as being simply based on the electrostatic repulsion of two fission products, you get essentially the same energy output in the form of kinetic energy. This is how the physics of fission is often taught in actual physics classes, because it gives you a more concrete indication of how that energy is getting released (whereas E=mc² with the mass-defect makes it seem like a magical lightning bolt carries it away). There are other more subtle physical questions involved in making a bomb, some of which have Einstein’s influence on them in one way or another (e.g. Bose–Einstein statistics). But I think it is not totally crazy to say that even if you somehow imagine a world in which Einstein had never existed, that the physics of an atomic bomb would still work out fine — Einstein’s specific technical work wasn’t central to the problem at all. We also have not brought up the question of whether without Einstein, relativity in some form would have been discovered anyway. The answer is probably “yes,” as there were people working on similar problems in the same areas of physics, and once people started paying a close attention to the physics of radioactivity they were bound to stumble upon the mass-energy relationship anyway. This isn’t to denigrate or underestimate Einstein’s influence on physics, of course. What makes Einstein “Einstein” is that he, a single person, pulled off a great number of theoretical coups all at once. But if he hadn’t done that, there’s no reason to think that other people wouldn’t have come up with his theoretical insights individually, if slightly later.

A postwar re-creation of the genesis of the Einstein-Szilard letter.

A postwar re-creation of the genesis of the Einstein-Szilard letter.

What about Einstein’s most direct role, the famous Einstein-Szilard letter of 1939 that influenced President Roosevelt to set up the first Uranium Committee? This is a tricky historical question that could have (and may at some point) an entirely separate blog post relating to it. Its writing, contents, and influence are more complex than the standard “he wrote a letter, FDR created the Manhattan Project” understanding of it that gets boiled down in some popular accounts. My feeling about it, ultimately, is this: if the Einstein-Szilard letter hadn’t been written, it isn’t clear that anything would be terribly different in the outcome in terms of making the bomb. Something like the Uranium Committee might have been started up anyway (contrary to popular understanding, the letter was not the first time Roosevelt had been told about the possibility of nuclear fission), and even if it hadn’t, it isn’t clear that the Uranium Committee was necessary to end up with a Manhattan Project. The road from a fission program whose primary output was reports and a fission program whose primary output was atomic bombs was not a direct one. By early 1941, the Uranium Committee had failed to convince scientist-administrators that atomic bombs were worth trying to build. They had concluded that while atomic bombs were theoretically feasible, they were not likely to be built anytime soon. Had things stayed there, it seems unlikely the United States would have built a bomb ready to use by July/August 1945.

The “push” came from an external source: the British program. Their MAUD Committee (an equivalent of the Uranium Committee) had concluded that a nuclear weapon would be much easier to build than the United States had concluded, and sent an emissary (Mark Oliphant) to the United States to make sure this conclusion was understood. They caught Vannevar Bush’s ear in late 1941, and he (along with Ernest Lawrence, Arthur Compton, and others) wrested control of the uranium work out of the hands of the Uranium Committee, accelerated the work, and morphed it into the S-1 Committee. The name change is significant — it is one of the more vivid demonstrations of the increased degree of seriousness with which the work was taken, and the secrecy that came with it. By late 1942, the wheels for the full Manhattan Project were set into motion, and the work had become a real bomb-making program.

Einstein wasn’t involved with any of the later work that actually led to the bomb. He almost was, though: in late 1941, Bush considered consulting Einstein for help on the diffusion problem, but opted not to push for it — both because Einstein wasn’t regarded as politically reliable (he had a fat FBI file), and his approach to physics just wasn’t very right for practical problems.3 Bush decided that Einstein would stay out of the loop.

Usual, rare anti-Nazi propaganda postcard from 1934, showing Hitler expelling Einstein from Germany, titled "The Ignominy of the 20th Century." It is one of the most blatant visual renderings of Einstein as a "scientific saint." Source.

Unusual, rare anti-Nazi propaganda postcard from 1934, showing Hitler expelling Einstein from Germany, titled “The Ignominy of the 20th Century.” It is one of the most blatant visual renderings of Einstein as a “scientific saint.” Source.

Let’s sum it up. Did Einstein play a role in the creation of the atomic bomb? Of course — his physics isn’t irrelevant, and his letter to Roosevelt did start one phase of the work. But both of these things are less prominent than the Time-magazine-cover-understanding makes them out to be. They weren’t central to what became the Manhattan Project, and if you could somehow, magically, remove Einstein from the equation, it isn’t at all clear that the atomic bomb wouldn’t have been built around the time it actually was built. I don’t think you can really credit, or blame, Einstein for the atomic bomb, in any direct fashion. Einstein did play a role in things, but that role wasn’t as crucial, central, or direct as a lot of people imagine. If you could magically drop him out of history, I think very little in terms of atomic bombs would have been affected.

So why does the Einstein and the bomb myth persist? Why does everybody learn about the Einstein letter, if it wasn’t really was sparked the Manhattan Project? There are two answers here, I think. One is that Einstein was, even before the war, one of the best-known, best-recognized physicists of the 20th century, and was synonymous with revolutionary science and genius. Having him “predict” the atomic bomb with equations in 1905 — 40 years before one was set off — is the kind of “genius-story” that people love, even if it obscures more than it enlightens. It also has a high irony quotient, since Einstein was forced to flee from Germany when the Nazis took power.

But there’s another, perhaps more problematic aspect. In many early copies of the Smyth Report that were distributed by the government, copies of the Einstein letter were mimeographed and loosely inserted. The magnification of Einstein’s role was purposefully encouraged by the government in the immediate period after using the weapon. (And it was even a convenient myth for Einstein, as it magnified his own importance and thus potential influence.) Hanging the atomic bomb on Einstein’s head was an act of self-justification, of sorts. Einstein was the world’s greatest genius in the eyes of the public, and he was a well-known pacifist, practically a scientific saint. After all, if Einstein thought building a bomb was necessary, who could argue with him?

Notes
  1. As Robert Serber puts it: “Somehow the popular notion took hold long ago that Einstein’s theory of relativity, in particular his famous equation E = mc², plays some essential role in the theory of fission. Albert Einstein had a part in alerting the United States government to the possibility of building an atomic bomb, but his theory of relativity is not required in discussing fission. The theory of fission is what physicists call a non-relativistic theory, meaning that relativistic effects are too small to affect the dynamics of the fission process significantly.” Robert Serber, The Los Alamos Primer: The First Lectures on How to Build an Atomic Bomb (University of California Press, 1992), 7. []
  2. For a good, non-teleological, non-bomb-centric approach to the context of 19th- and 20th-century physics, Helge Kragh’s Quantum Generations: A History of Physics in the Twentieth Century (Princeton University Press, 2002), is excellent. []
  3. Einstein wasn’t entirely a head-in-the-clouds physicist, of course. He worked at the patent office, and as Peter Galison has written about, even his famous thought experiments were often motivated by experience with practical problems of time synchronization. And he did help invent a refrigerator with Leo Szilard. But his work on diffusion physics was too abstract, too focused on first-principle analysis, for use in producing a practical outcome. []
Meditations

Feynman and the Bomb

Friday, June 6th, 2014

Richard Feynman is one of the best-known physicists of the 20th century. Most of those who know about him know he was at Los Alamos during the Manhattan Project — some of the best “Feynman stories” were set there. But Feynman’s own stories about his wartime hijinks were, like most of his stories about himself, half just-for-laughs and half lookit-mee! Feynman’s always got to either be a lucky average Joe, or the one brilliant mind in a sea of normals. His Los Alamos antics are mostly just tales of a genius man-child running around a secret laboratory, picking safes and irritating security guards. They aren’t very good gauges of what he actually did towards making the bomb. So what did Feynman actually do with regards to making the bomb? And does it matter, for thinking about his later career, especially the work that won him a Nobel Prize two decades later? 

Los Alamos colloquium from 1946, featuring (foreground, from left-to-right), Norris Bradbury, J. Robert Oppenheimer, John Manley, Richard Feynman, and Enrico Fermi. This version is cropped from the scanned copy at the Emilio Segrè Visual Archives. I will note that unlike the more common copies of this photo that have circulated, you can actually get a sense for how many other people were in the room — it looks like a really packed house.

Los Alamos colloquium from 1946, featuring (foreground, from left-to-right), Norris Bradbury, J. Robert Oppenheimer, John Manley, Richard Feynman, and Enrico Fermi. This version is cropped from the scanned copy at the Emilio Segrè Visual Archives. I will note that unlike the more common copies of this photo that have circulated, you can actually get a sense for how many other people were in the room — it looks like a really packed house.

Feynman’s own stories of his wartime work are centered around things other than the work itself. So he describes doing calculations, but doesn’t really say what they were for. He describes going to Oak Ridge, but only as a pretext for a story about dealing with generals and engineers. He describes the Trinity test, but a lot of that is about his claim to being the only person who saw it without welding glass on. And so on. These give glimpses, but not a very complete picture.

The historian of physics (and my advisor) Peter Galison wrote an article on “Feynman’s War” several years back, looking closely at what it actually was that Feynman was doing at the lab, and how it played into the style that he later became famous for in physics.1 Galison argues that Feynman’s postwar work is uniquely characterized by being “modular, pictorial, and proudly unmathematical.” He contrasts this with the work of several of his contemporaries, including Julian Schwinger, who came up with equivalent solutions to the same physical problems but through a very different (much more mathematical) approach. Feynman’s famous diagrams, which had a huge influence on the teaching and practice of postwar physics, exemplify this approach. What in Schwinger and Tomonaga’s hands (the other people Feynman shared his Nobel Prize with in 1965) was solvable only through massive, lengthy, laborious math could, in Feynman’s hands, be solved through a series of clever diagrams which came up with equivalent results. Feynman’s solutions to quantum electrodynamics weren’t the only way to do it — but they were easier to comprehend, to teach, and to apply to new questions.

The first Feynman diagram, published in R. P. Feynman, "Space—Time Approach to Quantum Electrodynamics,"Physical Review 76 (1949), 769-789, on 772.

The first published Feynman diagram, from Richard P. Feynman, “Space-Time Approach to Quantum Electrodynamics,”Physical Review 76 (1949), 769-789, on 772.

OK, so what does this have to do World War II? Well, Galison’s argument is that you can see the same sort of thinking at work in what Feynman did at Los Alamos, and he argues that it is during the war that he really started applying this mode of physics. He divides Feynman’s work into several “projects.” They were:

  • Neutron measurements for determining critical mass (including the famous “tickling the dragon’s tail” experiment” involving creating brief, barely-subcritical masses)
  • Work on the “Water Boiler” reactor at Los Alamos, which provided further data on nuclear chain reactions
  • Work as a safety supervisor at Oak Ridge, Tennessee, at Oppenheimer’s request (which in his own writings is distilled down to a single humorous anecdote where Feynman is simultaneously clueless and brilliant)
  • Developing formulae relating to criticality and implosion efficiency (including the Bethe-Feynman formula)
  • His work on the hydride bomb, an abortive, Teller-inspired approach to make a “cheaper” fission weapon which involved devilishly difficult calculation (because not all of the neutrons produced in the weapon would be of the same energy)

Galison argues that in each of these instances, you can see the germs of his later approaches. He credits this to both Feynman’s own personal scientific style and inclinations as a theorist (Feynman didn’t seem to like to work with fundamental equations, but with “shortcuts” that lead to quicker, more efficient solutions, for example), but also to the requirements of the wartime goal, where theorists had to come up with tangible, practical results in a very short amount of time.  For example, Galison notes that the formulae relating to how the implosion bomb worked “brought the abstract differential equations to the bottom line: how hot, how fast, how much yield?” The practical needs of the war favored a particular “theoretical style” in general, Galison argues, one that could be most easily meshed with engineering concerns, rapid prototyping, and the lack of time to ruminate on fundamental physics questions.2

The "Water Boiler" reactor at Los Alamos. Source: Los Alamos Archives (12784), via Galison 1998.

The “Water Boiler” reactor at Los Alamos that Feynman worked on. Source: Los Alamos Archives (12784), via Galison 1998, p. 404.

Galison’s article is fairly technical. He goes through Feynman’s work (what of it that is declassified, anyway) and tries to follow his thinking in a very “internal” way, and then match that up with the requirements imposed by the specific wartime context. If you are well-versed in physics you will probably find the details interesting. I’m more of a big-picture person myself, and I like the structure of Galison’s argument even if I don’t feel fully capable of digesting all of the physics involved. One small example of Galison’s work can probably suffice. Feynman was sent to Oak Ridge, as noted, to serve as a safety supervisor. He was taking over for Robert Christy, who got pneumonia in April 1944. The safety question was not a general one, but a very specific one: how many barrels of uranium (in various degrees of enrichment) could be safely stored in a room without running a risk of a criticality accident? Feynman himself relates the problem like this in his famous bit, “Los Alamos from Below” (reproduced in Surely You’re Joking, Mr. Feynman):

It turned out that the army had realized how much stuff we needed to make a bomb — twenty kilograms or whatever it was — and they realized that this much material, purified, would never be in the plant, so there was no danger. But they did not know that the neutrons were enormously more effective when they are slowed down in water. In water it takes less than a tenth — no, a hundredth — as much material to make a reaction that makes radioactivity. It kills people around and so on. It was very dangerous, and they had not paid any attention to the safety at all.

In Feynman’s account, he more or less walks in and figures out what the problems were and how to fix them. The story is about ignorance — in particular systemic ignorance due to secrecy — and Feynman’s attempts to cut through it.

Feynman's diagrammatic sketch of storage of barrels of uranium at Oak Ridge, prepared for his "Safety Report." Source: Galison 1998, p. 408.

Feynman’s diagrammatic sketch of storage of barrels of uranium at Oak Ridge, prepared for his “Safety Report.” Source: Galison 1998, p. 408.

Galison’s account is more technical. Feynman told them that pretty much any amount of unenriched uranium could be stored safely in the facility, but that 5% enriched and 50% enriched had to be handled fairly carefully. 50% enriched uranium in water, for example, would dangerous at a mere 350 grams of material unless there was a neutron absorbing material (cadmium) present. Feynman developed a series of safety recommendations for all grades of enrichments, and had to use reasonable safety margins to make up for potential errors in the calculations. He became the “point man” for safety questions involving fissionable materials, and developed (as Galison puts it) “visualizable” methods for answering basic (but important) questions about hypothetical systems (e.g. for “Gunk storage tanks,” whether they had to be coated with cadmium or not). His methods, Feynman himself emphasizes, were “only approximate, as accuracy has been sacrificed to speed and simplicity in calculation” — the kind of computational “short cut” that was both needed for the practical requirements, but also was common to Feynman’s general approach to physics. Galison concludes the section thus:

The admixture of approximation methods, neutron diffusion, nuclear cross sections, floods, fires and wooden walls marked Feynman’s correspondence with the Oak Ridge engineers. From April of 1944 to September 1945, whatever else Feynman was doing, he was also deeply enmeshed in the barely-existing field of nuclear engineering. Out of this interaction came characteristic rules and modular reasoning: visualizable, approximate, from-the-ground-up calculations applied to neutrons, pans, sheds and sludge. Visionary statements reinterpreting established laws of physics ceded to the exigencies of living in a world he had to reach outside the home culture of theoretical physics as he knew it before the war. Now a billion dollar plant was churning out U-235, and only a calculation stood between thousands of workers and nuclear disaster.

Which is a lot more serious-sounding that Feynman’s own somewhat jokey accounts of the work. In the latter part of the article, Galison connects all of these methods for thinking — and sometimes even the specific problems — with Feynman’s postwar work, showing the influence of his time at Los Alamos.

Diagram of neutron fluctuations from a report by F. de Hoffmann, R.P. Feynman, and R. Serber. Galison notes: "Significantly, Feynman and his collaborators captured the situation in a spacetime diagram drawn with time in the vertical direction and space horizontal. Such an image must be kept in mind when viewing Feynman's early postwar spacetime 'Feynman diagrams,' where again particles are absorbed, emit other particles, and scatter as reckoned by a concatenation of independent algebraic rules." Galison 1998, 405-406.

Diagram of neutron fluctuations from a report by F. de Hoffmann, R.P. Feynman, and R. Serber. Galison notes: “Significantly, Feynman and his collaborators captured the situation in a spacetime diagram drawn with time in the vertical direction and space horizontal. Such an image must be kept in mind when viewing Feynman’s early postwar spacetime ‘Feynman diagrams,’ where again particles are absorbed, emit other particles, and scatter as reckoned by a concatenation of independent algebraic rules.” Galison 1998, 405-406.

Feynman stayed at Los Alamos until the fall of 1946, when he relocated to Cornell University. He never worked on weapons again, but he never took a particularly strong stand on it. What did Feynman think about nuclear weapons, and his role in making them? There is some evidence in his private correspondence, much of which was published not too long ago,3 but it is scant. Most of his responses to inquiries were along the lines of “we feared the Nazis would get one first.”4That’s it. No comment on their use at all, or the end of the war, or any of the other common responses from Los Alamos veterans. When asked in the 1970s about his thoughts on nuclear weapons in general, he demurred: “Problems about the atomic bomb and the future are much more complicated and I cannot make any short  statement to summarize my beliefs here.”5

Feynman gave an interview in 1959 where he was asked directly about the bomb. His response was a little lengthier then, but still said very little:

Now, with regard to our own things as human beings, naturally—I myself, for example—worked on the bomb during the war. Now how do I feel about that? I have a philosophy that it doesn’t do any good to go and make regrets about what you did before but to try to remember how you made the decision at the time. …if the scientists in Germany could have developed this thing, then we would be helpless, and I think it would be the end of the civilization at that time. I don’t know how long the civilization is going to last anyway. So the main reason why I did work on it at the time was because I was afraid that the Germans would do it first, and I felt a responsibility to society to develop this thing to maintain our position in the war.6

This, of course, ignores the question of “so why did you continue when the Germans were known not to have made much progress?” and much more.

Charles Critchfield, Richard Feynman, J. Robert Oppenheimer, and an unidentified scientist, at Los Alamos. Source: Emilio Segrè Visual Archives, via Los Alamos.

Charles Critchfield, Richard Feynman, J. Robert Oppenheimer, and an unidentified scientist, at Los Alamos. Source: Emilio Segrè Visual Archives, via Los Alamos.

During the interview, Feynman was asked, point blank, whether he worked on any secret projects. Feynman said no, and that this was “out of choice.” Pushed further, he elaborated:

I don’t want to [do secret work] because I want to do scientific research—that is, to find out more about how the world works. And that is not secret; that work is not secret. There’s no secrecy associated with it. The things that are secret are engineering developments which I am not so interested in, except when the pressure of war, or something else like that, makes me work on it. … Yes, I am definitely anti-working in secret projects. … I don’t think things should be secret, the people developing this. It seems to me very difficult for citizens to make a decision as to what’s going on when you can’t say what you’re doing. And the whole idea of democracy, it seems to me, was that the public, where the power is supposed to lie, should be informed. And when there’s secrecy, it’s not informed. Now, that’s a naive point of view, because if there weren’t secrecy, there’d be the Russians who would find out about it. On the other hand, there’s some awfully funny things that are secret. It becomes secret that we know what the Russians are keeping secret from us, for instance, or something like that. It seems to me that things go too far in the secrecy.7

After that point in the interview, he steered away from political opinions, explaining that he had strong ones, but he didn’t think they were any more valuable than anyone else’s opinions.

There were those, of course, who did try to recruit Feynman for military work. John Wheeler, his doctoral advisor at Princeton, and the man who had roped him into Los Alamos in the first place, appealed to him strongly to join the Princeton work on the hydrogen bomb (Matterhorn) in late March 1951. Wheeler had heard the Feynman was trying to spend his sabbatical in Brazil, but Wheeler thought the chance of global war was “at least 40%,” and that Feynman’s talents might be better spent helping the country. It was a long, emotional letter, albeit a variation on one that Wheeler sent to many other scientists as well. Wheeler tried to win him (and others) with flattery as well, telling Feynman that “You would make percentage-wise more difference there than anywhere else in the national picture.” In response to Wheeler’s long, many-pointed letter, Feynman simply responded that he didn’t want to make any commitments until he found out whether the Brazil idea would work out. End of story. Nothing specific about the hydrogen bomb one way or the other.

High resolution detail of Feynman's Los Alamos security badge photograph. A this resolution you can see a lot more strain on his face than the one I posted awhile back. Source: Los Alamos National Laboratory Archives.

High-resolution detail of Feynman’s Los Alamos security badge photograph. At this resolution you can see potentially more strain on his face than the one I posted awhile back. Source: Los Alamos National Laboratory Archives.

What should we make of this? Feynman is a complicated man. Much more complicated than the zany stories let on — and I suspect the stories themselves were some kind of defense mechanism. As Feynman’s friend Murray Gell-Mann said at Feynman’s memorial service, Feynman “surrounded himself with a cloud of myth, and he spent a great deal of time and energy generating anecdotes about himself.” They were stories “in which he had to come out, if possible, looking smarter than anyone else.”8 He was not a moralizer, though. His work on the bomb fit into his stories only as a context. He no doubt drew many lessons from his work on nuclear weapons, and he no doubt had many opinions about them in the Cold War, but he kept them, it seems, much to himself.

Oppenheimer famously said that, “In some sort of crude sense, which no vulgarity, no humor, no overstatement can quite extinguish, the physicists have known sin…” Perhaps Feynman agreed — perhaps no more humor could be wrung out of the bomb after Hiroshima and Nagasaki. Maybe it’s harder to write a zany story about the hydrogen bomb. And maybe he was just truly not interested in them from a technical standpoint, or, as he said in 1959, just didn’t think his opinions on these matters, one way or another, were worth a damn, going against the notion held by many of his contemporaries that those who made the bomb had a special knowledge and a special responsibility. To me, he’s still something of an enigma, just one that wrapped himself in jokes, rather than riddles.

Notes
  1. Peter Galison, “Feynman’s War: Modelling Weapons, Modelling Nature,” Stud. Hist. Phil. Mod. Phys. 29, No. 3 (1998), 391-434. []
  2. This is an argument that Galison also makes at length about wartime work in his 1997 book Image and Logic: A Material Culture of Microphysics, both for Los Alamos and for the MIT Rad Lab, which if you’re interested in this kind of thing, is a must-read. []
  3. Michelle Feynman, ed., Perfectly Reasonable Deviations from the Beaten Track: The Letters of Richard P. Feynman (Basic Books, 2005). []
  4. See e.g., Ibid., 268: “I did work on the atomic bomb. My major reason was concern that the Nazi’s would make it first and conquer the world.” []
  5. Ibid., 305. []
  6. Ibid., 421. []
  7. Ibid., 422-423. []
  8. James Gleick, Genius: The Life and Science of Richard Feynman (Pantheon, 1992), on 11. []
Visions

Oppenheimer and the Gita

Friday, May 23rd, 2014

What was going through J. Robert Oppenheimer’s head when he saw the great fireball of the Trinity test looming above him? According to his brother, Frank, he only said, “it worked.” But most people know a more poetic account, one in which Oppenheimer says (or at least thinks) the following famous lines:

I remembered the line from the Hindu scripture, the Bhagavad-Gita; Vishnu is trying to persuade the Prince that he should do his duty and, to impress him, takes on his multi-armed form and says, “Now I am become Death, the destroyer of worlds.” I suppose we all thought that, one way or another.

This particular version, with a haggard Oppenheimer, was originally filmed for NBC’s 1965 The Decision to Drop the Bomb. I first saw it in Jon Else’s The Day After Trinity (1980), and thanks to YouTube it is now available pretty much anywhere at any time. There are other versions of the quote around — “shatter of worlds” is a common variant — though it did not begin to circulate as part of Los Alamos lore until the late 1940s and especially the 1950s.

It’s a chilling delivery and an evocative quote. The problem is that most of the time when it is invoked, it is done purely for its evocativeness and without any understanding as to what it actually supposed to mean. That’s what I want to talk about: what was Oppenheimer trying to say, presuming he was not just trying to be gnomic? What was he actually alluding to in the Gita?

An Indian greeting card for Diwali from 1998, celebrating India's nuclear tests. Source.

An Indian greeting card for Diwali from 1998, celebrating India’s nuclear tests. Source.

I should say first that I’m no scholar of Hindu theology. Fortunately, many years back, James A. Hijiya of the University of Massachusetts Dartmouth wrote a wonderful article on “The Gita of J. Robert Oppenheimer” that covers all of this topic as well as one might ever want it to be covered.1 Everything I know about the Gita comes from Hijiya’s article — so read it if you want much more discussion of this than I have here. I am particularly fond of Hijiya’s opening line, that Oppenheimer’s paraphrase of the Gita is “one of the most-cited and least-interpreted quotations” of the atomic age.

Oppenheimer was not a Hindu. He was not much of anything, religiously — he was born into a fairly secular Jewish family, embraced the Ethical Culture of Felix Adler, and saw philosophy as more of a boon to his soul than any particular creed. He enjoyed the ideas of the Gita, but he was not religious about it. Hijiya thinks, however, that much can be understood about Oppenheimer’s life through the lens of the Gita as a philosophical and moral code, something necessary in part because Oppenheimer rarely discussed his own internal motivations and feelings about making the bomb. It helps explain, Hijiya argues, that a man who could utter so many public statements about the “sin” and “terror” and “inhumanity” of Hiroshima and Nagasaki could also have been the one who pushed for their use against Japan and who never, ever said that he actually regretted having built the bomb or recommending its use. It helps resolve one of the crucial contradictions, in other words, at the heart of the story of J. Robert Oppenheimer.

J. Robert Oppenheimer, from the Emilio Segrè Visual Archives.

J. Robert Oppenheimer, from the Emilio Segrè Visual Archives.

It’s not clear when Oppenheimer was first exposed to the Gita. I have seen accounts, in oral histories, that suggested that he was spouting Gita lines even while he was a young graduate student studying in Europe. What is definitely known is that he didn’t start studying Sanskrit seriously until 1933, when he started studying with the renown Sanskrit scholar Arthur W. Ryder while he was a professor at Berkeley. In letters, he wrote gushingly about the book to his brother, and much later he quoted from it at the service held at Los Alamos in April 1945 upon the death of President Roosevelt.

The story of the Gita is that of Arjuna, a human prince who has been summoned to a war between princely cousins. Arjuna doesn’t want to fight — not because he lacks courage, or skill, but because it is a war of succession, so his enemies are his own cousins, his friends, his teachers. Arjuna does not want to kill them. He confides in his charioteer, who turns out to be the god Krishna2 in a human form. The text of the Gita is mostly Krishna telling Arjuna why Arjuna must go to war, even if Arjuna does not want to do it.

Krishna’s argument hinges on three points: 1. Arjuna is a soldier, and so it is his job — his duty — to wage war; 2. It is Krishna’s job, not Arjuna’s, to determine Arjuna’s fate; 3. Arjuna must ultimately have faith in Krishna if he is going to preserve his soul.

Arjuna eventually starts to become convinced. He asks Krishna if he will show him his godlike, multi-armed form. Krishna obliges, showing Arjuna an incredible sight:

Krishna revealing himself to Arjuna. Source.

Krishna revealing himself to Arjuna. Source.

A thousand simultaneous suns
     Arising in the sky
Might equal that great radiance,
     With that great glory vie.

Arjuna is awestruck and spellbound:

Amazement entered him; his hair
     Rose up; he bowed his head;
He humbly lifted folded hands,
     And worshipped God. . . .

And then, in his most amazing and terrible form, Krishna tells Arjuna what he, Krishna, is there to do:

Death am I, and my present task
     Destruction.

Arjuna, suitably impressed and humbled, then agrees to join in the battle.

The above quotes are from Ryder’s translation of the Gita. You can see that Oppenheimer’s is not especially different from that, even if it is somewhat changed. Personally I find Ryder’s version of the last part more impressive — it is more poetic, more stark. Ryder’s translation, Hijiya explains, is a somewhat idiosyncratic but defensible one. What Ryder (and Oppenheimer) translate as “Death,” others have translated as “Time,” but Hijiya says that Ryder is not alone for calling attention to the fact that in this context the expanse of time was meant to be a deadly one.

If you would like to see the famous “death” verse in the original, it is chapter 11, verse 32 of the Gita, and looks like this:

Gita verse 11:32

This website (from which I got the above) translates it as:

Lord Krsna said: I am terrible time the destroyer of all beings in all worlds, engaged to destroy all beings in this world; of those heroic soldiers presently situated in the opposing army, even without you none will be spared.

While I find Ryder’s more poignant, the longer translation makes it extremely clear what Krishna has in mind. All will perish, eventually. In war, many will perish whether you participate or not. For Oppenheimer and the bomb, this may have seemed especially true. The cities of Hiroshima and Nagasaki (and others on the target list) were on it not because they were necessarily the most important, but because they had so far been spared from firebombing. They were being actively preserved as atomic bomb targets. Had the bomb not been used or made, they probably would have been firebombed anyway. Even if the physicists had refused to make nuclear weapons, the death toll of World War II would hardly have been altered.

Trinity long exposure

“A thousand simultaneous suns”: a long-exposure shot of the Trinity test.

So let’s step back and ask who Oppenheimer is meant to be in this situation. Oppenheimer is not Krishna/Vishnu, not the terrible god, not the “destroyer of worlds” — he is Arjuna, the human prince! He is the one who didn’t really want to kill his brothers, his fellow people. But he has been enjoined to battle by something bigger than himself — physics, fission, the atomic bomb, World War II, what have you — and only at the moment when it truly reveals its nature, the Trinity test, does he fully see why he, a man who hates war, is compelled to battle. It is the bomb that is here for destruction. Oppenheimer is merely the man who is witnessing it. 

Hijiya argues that Oppenheimer’s sense of Gita-inspired “duty” pervades his life and his government service. I’m not sure I am 100% convinced of that. It seems like a heavyweight philosophical solution to the relatively lightweight problem of a life of inconsistency. But it’s an interesting idea. It is perhaps a useful way to think about why Oppenheimer got involved with so many projects that he, at times, seemed ambivalent about. Though ambivalence seemed readily available in those days — nobody seems to be searching for deep scriptural/philosophical justifications for Kenneth Bainbridge’s less eloquent, but equally ambivalent post-Trinity quote: “Now we’re all sons-of-bitches.”

A rare color photograph of Oppenheimer from October 1945, with General Groves and University of California President Robert Sproul, at the Army-Navy "E" Award ceremony. Source.

A rare color photograph of Oppenheimer from October 1945, with General Groves and University of California President Robert Sproul, at the Army-Navy “E” Award ceremony. Source.

One last issue that I find nagging me. We have no recording of Oppenheimer saying this except the 1965 one above. By this time, Oppenheimer is old, stripped of his security clearance, and dying of throat cancer. It is easy to see the clip as especially chilling in this light, given that is being spoken by a fading man. How would it sound, though, if it was coming from a younger, more chipper Oppenheimer, the one we see in photographs from the immediate postwar period? Would it be able to preserve its gravity?

Either way, I think the actual context of the quote within the Gita is far deeper, far more interesting, than the popular understanding of it. It isn’t a case of the “father” of the bomb declaring himself “death, the destroyer of worlds” in a fit of grandiosity or hubris. Rather, it is him being awed by what is being displayed in front of him, confronted with the spectacle of death itself unveiled in front of him, in the world’s most impressive memento mori, and realizing how little and inconsequential he is as a result. Compelled by something cosmic and terrifying, Oppenheimer then reconciles himself to his duty as a prince of physics, and that duty is war.

Notes
  1. James A. Hijiya, “The Gita of J. Robert Oppenheimer,” Proceedings of the American Philosophical Society 144, no. 2 (June 2000), 123-167. []
  2. Oppenheimer, in his 1965 interview, identifies the god as Vishnu, perhaps in error. Krishna is an avatar of Vishnu, however, so maybe it is technically correct along some line of thinking. []