Posts Tagged ‘Harry S. Truman’


Why Nagasaki?

Friday, August 9th, 2013

Today is the 68th anniversary of the atomic bombing of Nagasaki. Everyone knows that Nagasaki came three days after Hiroshima — but Nagasaki doesn't get talked about nearly as much. The reason Nagasaki gets "overlooked" is pretty obvious: being the second atomic bombing attack is a lot less momentous than the first, even if the total number of such attacks has so far been two.

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

A temple destroyed by the bombing of Nagasaki. Original source. Slightly edited to improve foreground/background distinction.

We all know, or think we know, why Hiroshima was bombed. This is because the bombing of Hiroshima is synonymous with the use of the atomic bomb in general. But why was Nagasaki bombed?

I don't mean, why the city of Nagasaki as opposed to another city. That is well-known. Nagasaki only made it on the list after Kyoto was removed for being too much of an important cultural center. The initial target on August 9 was Kokura, but there was too much cloud cover for visual targeting, so the Bockscar moved on to the backup target, nearby Nagasaki, instead. Bad luck for Nagasaki, twice compounded.

What I mean is: Why was a second atomic bomb used at all, and so soon after the first one? Why wasn't there more of a wait, to see what the Japanese response was? Was less than three days enough time for the Japanese to assess what had happened to Hiroshima and to have the meetings necessary to decide whether they were going to change their position on unconditional surrender? What was the intent?

There are, unsurprisingly, a number of theories about this amongst historians. There are some that think Nagasaki was justified and necessary. There are also many who agree with the historian Barton Bernstein, who argued that: "Whatever one thinks about the necessity of the first A-bomb, the second — dropped on Nagasaki on August 9 — was almost certainly unnecessary."1 And there are those, like Tsuyoshi Hasegawa, who don't think either of the atomic bombings had much effect on the final Japanese decision to unconditionally surrender when they did. (I will be writing a much longer post on the Hasegawa thesis in the near future — it deserves its own, separate assessment.)

The following images are screens taken from footage taken of the Fat Man preparations on Tinian, courtesy of Los Alamos National Laboratory. Above, preparing the final weapon, sealing the ballistic case joints with red Pliobond and blue Glyptol (plastic film). The different colors made it clear that they were properly applied and overlapped.

The following images are screens taken from footage taken of the Fat Man preparations on Tinian, courtesy of Los Alamos National Laboratory. Above, preparing the final weapon, sealing the ballistic case joints with red Pliobond and blue Glyptol (plastic film). The different colors made it clear that they were properly applied and overlapped.

The first is the standard, "official" version — the second bomb was necessary to prove that the United States could manufacture atomic weapons in quantity. That is, the first atomic bomb proved it could be done, the second proved it wasn't just a one-time thing. One wonders, of course, why anyone would think the Japanese would think the atomic bomb was a one-off thing, or that the Americans wouldn't have the resolve to use it again. They had, after all, shown no flinching from mass destruction so far — they had firebombed 67 Japanese cities already — and while making an atomic bomb was indeed a big effort, the notion that they would be able to make one and no more seems somewhat far-fetched. The idea that the US would have a slow production line isn't far-fetched, of course.

What did the participants in the decision to bomb have to say about the use of specifically two bombs? General Groves told an interviewer in 1967 that: was not until December of 1944 that I came to the opinion that two bombs would end the war. Before that we had always considered more as being more likely. Then I was convinced in a series a discussions I had with Admiral Purnell.2

Which, if true, would peg this decision fairly early in the process. In his memoirs, Groves also has this little exchange from just after the "Trinity" test:

Shortly after the explosion, [Brig. General Thomas] Farrell and Oppenheimer returned by jeep to the base camp, with a number of others who had been at the dugout. When Farrell came up to me, his first words were, "The war is over." My reply was, "Yes, after we drop two bombs on Japan."3

Both of these, of course, are recollections made long after the fact. And Groves is known to have "smoothed" his memories in order to present him in the best possible light to posterity. The actual instructions for the use of the bomb, from late July 1945, only give detailed information about the first bomb:

1. The 509 Composite Group, 20th Air Force will deliver its first special bomb as soon as weather will permit visual bombing after about 3 August 1945 on one of the targets: Hiroshima, Kokura, Niigata and Nagasaki. [...]

2. Additional bombs will be delivered on the above targets as soon as made ready by the project staff. Further instructions will be issued concerning targets other than those listed above.4

President Truman, in his diary entry, referred to the impending use of the atomic bomb as a singular thing. In his public statements after Hiroshima (which he probably did not write), he claimed that many more atomic bombs would be used until the Japanese surrendered. That being said, he did put a "stop" on any further bombing on August 10th, to wait for a response. This didn't have any immediate consequences on Tinian, since the next, third bomb wouldn't have been ready for a few more weeks, and even then, it wasn't clear whether it would have been immediately dropped or "saved" for a multi-bomb raid.

The bomb prepared, it was then sheathed in canvas and towed out to the loading bay. I find the shot on the right particularly ominous — the second bomb, still a secret, its size and probable importance not quite masked by its shroud.

The bomb prepared, it was then sheathed in canvas and towed out to the loading bay. I find the shot on the right particularly ominous — the second bomb, still a secret, its size and probable importance not quite masked by its shroud.

Oppenheimer, for his part, seems to have expected that both "Little Boy" and "Fat Man" units would be used in combat. In a memo sent on July 23, 1945, Oppenheimer explicitly discussed the expected performance of "the first Little Boy and the first plutonium Fat Man." Notably, he expressed near complete confidence in the untested Little Boy:

The possibilities of a less than optimal performance of the Little Boy are quite small and should be ignored. The possibility that the first combat plutonium Fat Man will give a less than optimal performance is about twelve percent. There is about a six percent chance that the energy release will be under five thousand tons, and about a two percent chance that it will be under one thousand tons. It should not be much less than one thousand tons unless there is an actual malfunctioning of some of the components.5

Which raises the interesting secondary question of why Little Boy went first and Fat Man went second. Was it because Little Boy was the more predictable of the two? There's very little about this that I've seen in the archives — it seems like it was taken for granted that the gun-type would be the first one. Groves claimed later that the order was just an issue of when things ended up ready to be used on the island, but the components for both were available on Tinian by August 2, 1945, in any event.6

Oppenheimer had, interestingly, earlier suggested to Groves that perhaps they ought to disassemble the 64 kg enriched-uranium core of Little Boy and use it to create a half-dozen enriched-uranium Fat Man bombs. Groves rejected this:

Factors beyond our control prevent us from considering any decision other than to proceed according to existing schedules for the time being. It is necessary to drop the first Little Boy and the first Fat Man and probably a second one in accordance with our original plan. It may be that as many as three of the latter in their best present condition may have to be dropped to conform with the planned strategic operations.7

All of which is to say that the Los Alamos people seemed to assume without question that at least two bombs would be necessary and would be used. At the higher levels, while Truman did publicly proclaim that further atomic bombings were follow, it isn't terribly clear he was clued in on the actual schedule of those which followed the first. I wonder if his order to stop bombing, issued immediately after Nagasaki (and the Soviet declaration of war on Japan) wasn't partially a reaction to the fact that he suddenly felt out of control of the military situation over there.

On the left, the bomb being unshrouded, just before loading into the B-29, Bockscar. On the right, the results: the fireball and mushroom cloud, seen through the window of one of the B-29s on the Nagasaki raid, just a few seconds after detonation, roiling and rapidly rising.

On the left, the bomb being unshrouded, just before loading into the B-29, Bockscar. On the right, the results: the fireball and mushroom cloud, seen through the window of one of the B-29s on the Nagasaki raid, just a few seconds after detonation, roiling and rapidly rising.

The historian Stanley Goldberg proposed another theory: that two bombs were necessary in order to justify the decision to pursue both the uranium and plutonium routes.8 That is, Little Boy would justify the (enormous) expense of Oak Ridge, and Fat Man would justify Hanford. To support this argument, Goldberg points out that during the war Groves was completely afraid of being audited by Congress in the postwar. Groves knew he was engaged in a huge gamble, and he also knew he had made a lot of enemies in the process. This is one of the reasons that he meticulously documented nearly every decision made during the Manhattan Project — he wanted "evidence" in case he spent the rest of his years being subpoenaed.9 It's a clever argument, though it relies heavily on supposition.

Michael Gordin has argued that this entire question revolves around a false notion: that it was known ahead of time that two and only two bombs were to be used. That is, instead of asking, why were two, and not one, used, Gordin instead looks into why were two, and not three, four, and etc. usedGordin's book, Five Days in August, argues that it was assumed by Groves and the other planners (but not necessarily Truman) that many more than two bombs were going to be necessary to compel Japan to surrender — that the surprising thing is not that the bombing cycle continued on August 9, but that Truman stopped the bombing cycle on August 10.10

Of these options, I tend to lead towards Gordin's interpretation. The decision-making process regarding the atomic bomb, once the Army took over the production side of things, was that they would be used. That is, not that it would be used, though the importance of the first one, and all of the import that was meant to be attached to it, was certainly appreciated by the people who were planning it. But it was never intended to be a one-off, once-used, anomalous event. It was meant to be the first of many, as the atomic bomb became yet another weapon in the US arsenal to use against Japan. The use of the bomb, and continued bombings after it, was taken by Groves et al. to be the "natural" case. To stop the atomic bombing would have been the unusual position. Go back to that original target order: the only distinction is between the "first special bomb" and the "additional bombs," not a singular second special bomb.

So "Why did they bomb Nagasaki?" might not be the right question at all. The real question to ask might be: "Why did they stop with Nagasaki?Which, in a somewhat twisted way, is actually a more hopeful question. It is not a question about why we chose to bomb again, but a question about why we chose not to.

  1. Barton J. Bernstein, "The Atomic Bombings Reconsidered," Foreign Affairs 74, no. 1 (1995), 135-152, on 150. []
  2. Quoted in Robert S. Norris, Racing for the Bomb: General Leslie R. Groves, the Manhattan Project's Indispensable Man (Steerforth, 2003), 655 fn. 29. []
  3. Leslie R. Groves, Now it Can be Told (Harper, 1962), 298. []
  4. General Thomas Handy to General Carl Spaatz (25 July 1945),  U.S. National Archives, Record Group 77, Records of the Office of the Chief of Engineers, Manhattan Engineer District, TS Manhattan Project File '42 to '46, Folder 5B. Copy online here. []
  5. J. Robert Oppenheimer to Thomas Farrell (23 July 1945), copy in the Nuclear Testing Archive, Las Vegas, NV, document NV0103571. []
  6. Groves, Now it Can be Told, 308. All of the Little Boy components were on the island by July 28. The Fat Man core and initiator were on Tinian by July 28, and the HE pre-assemblies arrived on August 2. []
  7. Leslie Groves to J. Robert Oppenheimer (19 July 1945), copy reproduced in John Coster-Mullen, Atom Bombs: The Top Secret Inside Story of Little Boy and Fat Man. []
  8. Stanley Goldberg, “General Groves and the atomic West: The making and meaning of Hanford,” in Bruce Hevly and John Findlay, eds., The atomic West (University of Washington Press, 1998),  39-89. []
  9. And, in fact, he did end up needing some of those records when he was asked to testify at various times. But the scandals weren't what Groves had guessed they would be: they weren't about waste, but about people. Groves ended up drawing on his classified Manhattan Project History file when testifying about Klaus Fuchs and, later, J. Robert Oppenheimer. []
  10. Michael Gordin, Five Days in August: How World War II Became a Nuclear War (Princeton University Press, 2007). []
Meditations | Redactions

The Decision to Use the Bomb: A Consensus View?

Friday, March 8th, 2013

One of the great historical arguments of the late-20th century was whether the decision to use the atomic bomb was justified or not, and what the real goals of its use were. I've sometimes seen this dismissed by partisans (usually in favor of the use of the bomb) as being a recent sort of argument, only made by people who were well distanced from World War II, but this isn't the case. People were arguing loudly about this almost immediately. The ambivalence about the use of the bomb was nearly immediate, and even the Japanese were aware of such discussions taking place in the United States a month later.

This was why, in 1947, Secretary of War Henry Stimson put his name on an article in Harpers that February 1947 titled "The Decision to Use the Atomic Bomb" -- it was meant to be the "official" response to the on-going debates and speculation. General Groves, of course, had a heavy role in the composition of the article, not only because he was the guy who had all of the documents at hand, but because it was his legacy on the line, too. In fact, Groves seems to have been fairly responsible for pushing Stimson to publishing something on the subject, even offering up multiple pre-fab drafts drafts for Stimson in November 1946:1

Click the image for the full set of drafts.

Click the image for the full set of drafts.

Personally, I don't wade into these questions much, professionally, or even here on the blog. They honestly don't interest me very much. Maybe it's a sign of how post-post-Cold War I am? I don't know. To me it has always seemed like splitting very fine hairs, trying to make distinctions without much difference. In my mind, the atomic bombings were plainly not ethically very different than the previous firebombings of Japan or Germany. To argue about whether they were justified or not seems to me to be the wrong question — a question that misleads us into mistaking what the core issue was.

For me, the better question is, under what circumstances do we believe the use of weapons of mass destruction on civilians is justified?  That gets one into much more interesting ethical territory, in my opinion, than asking why the bombs were used, a question that seems to presume that the motivations are somehow the most important thing to ask about. It also keeps us from having the same old discussion that people have been having for nearly 70 years. Maybe it's my post-postness talking, here, but whether people in the past had better or worse intentions before setting a hundred thousand people on fire seems like the least interesting historical question to pose in the face of such actions.

1945: Tokyo at left, Hiroshima at right. Is there a significant moral difference?

Ruins of 1945: Tokyo at left, Hiroshima at right.

Nevertheless, I do pay some attention to these arguments, mostly because I get asked about this sort of thing from time to time (one of the hazards of being an historian of such matters) and it helps to have a snappy answer or two. So I was really interested to hear, at a workshop in DC a few weeks ago convened by the Atomic Heritage Foundation (more on the workshop and its purpose in a later post), the retired NRC historian J. Samuel Walker give a brief talk on the current state of the historiography over the "decision to use the bomb." Walker wrote an article on this subject in 1990a book in 1997, and another historiographical review in 2005.

I hadn't met Walker before this, but I've reviewed two of his books (one on Three Mile Island, another on US nuclear waste policy), and had appreciated and drawn upon his work as an historian. Walker is, as he put it, "a flaming moderate," and it comes out in his work. Both of those books are great — for TMI, he has a nice balance of technical detail with political/bureaucratic considerations (and a great chapter on the long-term effects on the nuclear industry); for nuclear waste, he does a great job of being strictly factual while pointing out exactly where he saw the US government underestimating the problem and failing to appreciate how much they were losing public faith. As with all moderates, he runs the risk of disappointing partisans of all sides, but that's the nature of it.

Portraits from Time magazine covers, 1945: Stalin, Truman, Hirohito.

Portraits from Time magazine covers, 1945: Stalin, Truman, Hirohito. Each kind of tacky in their own way, each kind of brilliant in their own way.

Walker mapped out two major poles on the "decision to use the bomb" question. (I should say up front that this is my synthesis of Walker's synthesis, re-written from memory. So it's possible I may be inadvertently mangling this a bit, though I don't think I am. There are other sub-arguments to this debate, of course, but to me this boils it down to the really crucial bits nicely.) The first is the "traditional" argument, which roughly follows the position put forward by Stimson in 1947. At its core, it argues, in brief:

  • that Truman made a decision to use the bomb on the basis of ending the war quickly;
  • the as far as the US was concerned, Japan would not surrender on acceptable terms without either the bomb or invasion;
  • and that of those two options, the bomb was the option that would cost the least number of American and Japanese lives;
  • and, as the Japanese Emperor acknowledged in his surrender statement, the bomb did in fact end the war promptly.

This is, of course, the argument that most people are familiar with. The other pole, according to Walker, is what is often called the "revisionist" take, a term acknowledged as potentially disparaging, and is expressed most forcefully in the work of Gar Alperovitz. At its core, it argues, in brief:

  • that Japan was already defeated at the time the decision to use the bomb was made, and that US intelligence already knew this;
  • that Japan had been suing for peace and was ready to surrender without an invasion;
  • that the real reason the bomb was used was so to demonstrate its power to the Soviet Union, in an attempt to exert more influence on them in the postwar;
  • and that Japanese Emperor's surrender statement invoked the bomb only as a politically-acceptable "excuse" for his people, when actually he surrendered primarily because of the Soviet invasion of Manchuria.

There are, of course, more details that people have hashed out over the years, including the infamous "how many casualties in an invasion" question. In the 1990s in particular, these were fiercely debated. It was, of course, the immediate post-Cold War, and everybody was still in a mood of assessment of trying to make out what the Cold War's legacy actually was.

So where are we now, firmly in the 2010s? Walker reported that in his assessment, the scholarly debate had cooled down quite a bit, and that a new consensus was emerging, something that could be visualized firmly in between the two poles. There were problems, he argued, with both the "traditional" and the "revisionist" views. Specifically:

  • It's not really clear that Truman ever made much of a "decision," or regarded the bomb/invasion issue as being mutually exclusive. Truman didn't know if the bomb would end the war; he hoped, but he didn't know, couldn't know. The US was still planning to invade in November 1945. They were planning to drop as many atomic bombs as necessary. There is no contemporary evidence that suggests Truman was ever told that the causalities would be X if the bomb was dropped, and Y if it was not. There is no evidence that, prior to the bombings of Hiroshima and Nagasaki, that Truman was particularly concerned with Japanese causalities, radiation effects, or whether the bombs were ethical or not. The entire framing of the issue is ahistorical, after-the-fact, here. It was war; Truman had atomic bombs; it was taken for granted, at that point, that they were going to be used. 
  • Defeat is not surrender. Japan was certainly defeated by August 1945, in the sense that there was no way for them to win; the US knew that. But they hadn't surrendered, and the peace balloons they had put out would have assumed not that the Emperor would have stayed on as some sort of benign constitutional monarch (much less a symbolic monarch), but would still be the god-head of the entire Japanese country, and still preserve the overall Japanese state. This was unacceptable to the US, and arguably not for bad reasons. Japanese sources show that the Japanese military was willing to bleed out the country to exact this sort of concession from the US.
  • American sources show that the primary reason for using the bomb was to aid in the war against Japan. However, the fact that such weapons would be important in the postwar period, in particular vis-à-vis the USSR, was not lost on American policymakers. It is fair to say that there were multiple motivations for dropping the bomb, and specifically that it looks like there was a primary motivation (end the war) and many other "derivative" benefits that came from that (postwar power).
  • Japanese sources, especially those unearthed and written about by Tsuyoshi Hasegawa, make it clear that prior to the use of the atomic bombs, the Japanese cabinet was still planning on fighting a long battle against invasion, that they were hoping to exact the aforementioned concessions from the United States, and that they were aware (and did not care) that such an approach would cost the lives of huge numbers of Japanese civilians. It is also clear that the two atomic bombs did shock them immensely, and did help break the stalemate in the cabinet — but that the Soviet invasion of Manchuria also shocked them immensely, perhaps equally, maybe even more (if you have a choice between being occupied by Truman or occupied by Stalin, the decision is an easy one). But there is no easy way to disentangle the effects of the bombs or the Soviet invasion, in this sense -- they were both immensely influential on the final decision. That being said, using the bomb as an "excuse" (as opposed to "we are afraid of Russians") did play well with the Japanese public and made surrender appear to be a sensible, viable option in a culture where surrender was seen as a complete loss of honor.

So what we're left with is something that, in my view, looks a lot more plausible than either the "traditional" or "revisionist" options, both of which assume way more prescience than actual historical actors usually have. (Much less Truman, of all people. In my view, even wondering what Truman thought about this is the wrong question to ask -- Truman was many things, but he was not a thoughtful guy. He makes Eisenhower look like a French philosopher by comparison.)

One of the more post-modern Time magazine covers — where the atomic bomb unseats Truman as Man of the Year.

One of the more post-modern Time magazine covers — where the atomic bomb unseats Truman as Man of the Year. Or something.

The are genres of historical explanation that people find compelling. This is something that goes a bit beyond the historical facts themselves: it is the superstructure in which we interpret the facts, or, to put it another way, it is how we think about everything that's going on that doesn't end up in the archival record.

What I find compelling about Walker's "consensus" view is that it is much more of a muddle than either the "traditional" view or the "revisionist" view. The "traditional" view makes it look like Truman et al. were making carefully reasoned decisions based on an ethics of the bomb that had not developed, based on questions that were not yet being asked. I don't really believe for a minute that Truman worried much about the first use of the atomic bomb. But the "revisionist" view makes him still look too clever by half — too scheming, too anticipatory, too prescient about both the Japanese war and the Cold War. That's not the Truman I know. The "consensus" view is much more human looking: the people in it are half-way acting consciously, half-way caught up in things that had been going on for a long time and were by then out of their active control. Of course, in retrospect, everyone wants to re-write history to make them look better, especially when they're being criticized for past actions. That's part of being human, too.

Walker also posited that along with this emerging consensus, there was also a cooling in the tone of the debate. This was immediately proved to be somewhat premature, as Peter Kuznik, another attendee to the workshop (who I consider a friend), vigorously defended the "revisionist" point of view. Well, so it goes -- there's no better way to prove an argument among scholars than to propose that there really isn't much of an argument anymore. Still, I found Walker's synthesis a useful way of framing the field of historical argumentation, summing up a number of disparate positions (each with books and books of documents and footnotes debating each tiny point) in a fairly convenient format. And what can I say -- I'm a sucker for moderate, synthetic arguments.

  1. Citation: Leslie R. Groves to Harvey H. Bundy, drafts of "The Decision to Use the Atomic Bomb" (6 November 1945), 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 5, Folder 20, "Miscellaneous." []

What If Truman Hadn’t Ordered the H-bomb Crash Program?

Monday, June 18th, 2012

The debate over the hydrogen bomb is one of my favorite Cold War episodes. I keep coming back to it, both on the blog and in my research. I'd posit that it is in many ways a lot more interesting than the debates about Hiroshima and Nagasaki. Why? Because at the time of the Second World War, there was actually very little debate about Hiroshima and Nagasaki. You basically had the Franck Report and the Targeting Committee; the former said, "don't drop it," and the latter replied, "who cares what you think? We're dropping it." As many have pointed out, the whole idea that there was a conscious "decision to drop the atomic bomb" is a bit off — it doesn't appear that anybody who had the authority to drop the bomb agonized over the question before dropping it. What agonizing there was mostly came after the fact.

The H-bomb was something else, though. This was a technical possibility that had been seen long before the weapon was capable of being built, and there actually was a period of serious behind-the-scenes and later public debate over whether it should be built, in an era where the potential guilt of Hiroshima and Nagasaki was still palpable. A lot of scientists saw the hydrogen bomb as an opportunity for the moral debate they never had about the atomic bomb, and that makes it, to me, a much more interesting co-mingling of visions of the past and fears of the future.

The ultimate "What If?" of the atomic bomb is, "what if they didn't drop the bomb?" The ultimate "What If?" of the H-bomb is, what if Truman hadn't ordered the crash program in late January 1950? 

The common Cold War argument was one of technological inevitability: if the H-bomb could be built, it would be built. This was then mixed with an existential plea: it would have been "intolerable" for the USSR to have an H-bomb and the USA not to. But let's shelve these common arguments for a minute, because, while interesting, they obscure a somewhat more basic factual question about what would have happened. I think that the incredible US superiority in both fission bombs and in delivery mechanisms would have easily deterred an H-bomb attack from the USSR, personally, and there are lots of ways to imagine the could/would transition could be avoided or stalled, but frankly, I think both of those questions are actually irrelevant to what would have occurred. 

There's a brief timeline that we all have to know to be on the same page here, so let's just throw it out in bulleted form:

  • August 1949: USSR tests its first bomb in a test the US dubs "Joe-1." The US detects it in September. Secret debate begins within US government over whether an H-bomb should be built. Debate leaks to public by end of 1949.
  • Late January 1950: Truman announces publicly that the Atomic Energy Commission should work to build an H-bomb.
  • March 1951: Edward Teller and Stanislaw Ulam figure out how to make a multi-megaton H-bomb.
  • May 1951: The basic principle of the Teller-Ulam design is tested at the Greenhouse GEORGE test in the Pacific Ocean. Also tested is Greenhouse ITEM, a "boosted" bomb whereby a tiny amount of fusion fuel is used to improve the efficiency of a fission bomb. "Boosted" bombs greatly increase the yield of existing weapons and/or allow you to make more weapons with less fissile material.
  • November 1952: The US tests its first Teller-Ulam style H-bomb, Ivy MIKE (10 Mt). It also tests Ivy KING, the largest pure-fission weapon ever built (500 kt; half a megaton). The Ivy MIKE device is a proof-of-concept; it weighed over 50 tons. (A handful of  potentially-deliverable prototypes were made based on the design, but it isn't clear whether they were considered reliable.)
  • August 1953: The USSR tests "Joe-4," a nuclear weapon that involves some fusion reactions but was not a "true" H-bomb. It was a very big bomb (400 kt, still less than the all-fission Ivy KING), but the design could not be scaled into the megaton range. Still, a big bomb, and it could be dropped from existing Soviet bombers.
  • March 1954: The US begins a test series of deliverable high-yield thermonuclear weapons, Operation Castle. Castle BRAVO, the first test in the series, was considerably larger in yield than was expected (15 Mt) and was one of the worst radiological accidents in US testing history. The US now has weaponized H-bombs in the multi-megaton range.
  • November 1955: The USSR tests its own multi-megaton H-bomb for the first time (RDS-37); it is deliverable.

That's the history we're really concerned with. Herbert York, in 1975, wrote an article in Scientific American about this question, the gist of which was later published as a book, The Advisors: Oppenheimer, Teller, and the Superbomb (San Francisco: W. H. Freeman, 1976). Most of the book and article concern the October 1950 report by the AEC's General Advisory Committee which was unfavorable to the idea of building the H-bomb and led to Oppenheimer's security hearing some years later. But what I really love about the Scientific American article, as opposed to the book that came out, are his illustrated timelines.1

The above is a modified version of the Scientific American timeline, and describes the events shown up above in bullet points. I've added a few small things to it — the period of the H-bomb debate itself (the endpoint is Truman's announcement; the debate technically goes on after that though it is a pretty done deal from a policy perspective), and the asterisk on the US "side" of the timeline shows when the US learned the Teller-Ulam idea, and the asterisk on the Soviet side is supposedly when the USSR figured it out for themselves. (Exactly when the Soviets actually figured it out, and how, is a matter of some continuing dispute.) The colors indicate the bomb type as indicated by the chart (they are not as distinct in the scan as the original), and the size of the circles indicate relative yield.

I like two things about this timeline. The first is that it shows how relatively close these events were to one another — two years (say, 1950 to 1952, or 1952 to 1954) seems like a long time until you stack it up like this, when it seems almost immediate. But the other thing comes what York (or, rather, the graphics editors at Scientific American, who worked quite independently from the authors at this period of time) does next: he proposes alternate possibilities.

Let's imagine, says, York, that Truman doesn't order an H-bomb built. What's the most probable outcome? Here's what he gives in response (I've modified this to fit onto the "original" timeline above; in York's it is a series of branching timelines):

In York's view, this "most probable alternative world," without the Truman decision, the US would still have developed ITEM (the "boosted" bomb) and KING (the all-fission bomb, which he says would have likely even been tested earlier, since the tempo of Operation Ivy was set by the time it took to get MIKE together). Let's imagine the Soviets still tested "Joe-4," which was, again, not a "true" multi-megaton H-bomb. York thinks that at that point, the US would have then initiated a "crash" H-bomb project, and pulled off a GEORGE-like test in late 1954, and probably a full-scale H-bomb in 1955 or 1956. (The MIKE/BRAVO distinction is whether it would have been liquid or solid fueled; hard-to-deliver or easier-to-deliver.)

Interestingly, York also thinks that the Soviets' development of a multi-megaton H-bomb would have been delayed. Why? Because in his view they got a lot of "stimulus" from the 1952 test, knowing that it was possible to work in the first place. Once you know something is achievable, for whatever reason, you end up finding the solution pretty quickly. (This is not unlike, but not quite the same thing, as the technological inevitability argument.) There is also (but York doesn't propose this) the possibility that the MIKE shot more directly helped the USSR in the way of fallout, as was speculated by Daniel Hirsch and William G. Mathews in the Bulletin of the Atomic Scientists awhile back now.2 The Soviets later claimed that they bungled the fallout analysis, but one never really knows.

So in York's "most probable" scenario, the US still would have had a real H-bomb well before the USSR. It's hard to see "Joe-4" as creating a strong strategic imbalance, especially since the US still would have had a bomb that big ready to go (KING).  OK, York says, maybe that's optimistic. What's the worst possible scenario? Another timeline:

In this timeline, we use the "real world" Soviet testing timeline with the "most probable" US reaction timeline. The result is that the Soviets have their first H-bomb at just about the same time that the US would have had one. That is, even in the worst-case scenario, the US and the USSR more or less have multi-megaton H-bombs at the same time. Not much imbalance to be held, especially if you take it into account that the US still had a huge advantage in fission weapons (3057 to 200 in 1955) and deliverability (bases in close proximity, long-range bombers).

All of these scenarios, of course, presume that the USSR would have soldiered on ahead with the H-bomb even if the US had renounced building it. That is, these are by definition all pessimistic scenarios — and none of them are that bad. One wonders what truly optimistic scenarios would have looked like!

The first "true" Soviet H-bomb test, 1955.

I like this way of using the timelines, though it flattens a lot. Would Teller and Ulam have come up with the Teller-Ulam idea without the Truman "crash" program? There's a lot to unpack there in terms of chronology — they didn't come up with it by just sitting around idly. Did the "crash" program really speed up development? A big, deep, difficult question. (In other words, are the asterisks on the modified "real" timeline actually fixed positions or are they relative to other things, and if so, to what?)

But still, even while this timeline approach doesn't quite cover all the bases, I still think it helps us play with the dates here a bit better, and visually play with the possibilities ("most probable" and "worst possible") in a provocative way. The "flattening" effect of the timeline is by design. I'm all for thick description (as you can tell), but sometimes there's an analytical advantage to being able to smooth things out to try and see the big pictures.

I'm more or less convinced that the world wouldn't have ended if Truman hadn't ordered the H-bomb's development. Heck, even if the USSR did have exclusive possession of multi-megaton H-bombs, I still don't see it affecting the strategic situation in a completely "intolerable" way — I don't see the USA ever thinking its fission deterrent wasn't able to deter. But the beauty of this way of thinking about it is that you don't even have to have that discussion, really, because it's not clear that possibility was ever on the table.

  1. Herbert York, "The Debate over the Hydrogen Bomb," Scientific American 233 (October 1975), 106-113. A copy is reprinted in York's Arms and the Physicist, for those who don't have access to Scientific American back issues. []
  2. Daniel Hirsch and William G. Mathews, "The H-bomb: Who Really Gave Away the Secret?" Bulletin of the Atomic Scientists 46, no. 1 (January 1990), 22-30. []

The Ivy MIKE leak

Wednesday, June 13th, 2012

On November 1, 1952, the United States detonated the world's first hydrogen bomb.1 Shot MIKE of Operation Ivy was the culmination of nearly a decade of work on developing thermonuclear weapons, and it released an explosive force equivalent to 10.4 million tons of TNT — some 800 times the explosive force of Hiroshima, capable of setting fire to an area of over a thousand square miles. 

The world had entered the megaton age, but the United States didn't want anybody to know about it.

Which is an odd thing, if you think about it. It's true, the first atomic bomb test — "Trinity" — had been kept a secret at the time. But only because the U.S. planned to use it on Japan quickly and wanted it to be a surprise. There was no "operational" reason for keeping the MIKE test a secret, except for the fact that, well, it wasn't actually really ready for prime-time, as far as weapons went. MIKE was a big, clunky cryogenic test apparatus that weighed over 50 tons. It had been designed (by Dick Garwin) to prove a point, not to fit on an airplane. They did manage to scale it down a bit as five "Emergency Capability" weapons (the "Jughead" bombs), but these required specialized plane modifications to field (and only one plane was so modified), and even then, one wonders how reliable they were considered. (And even these weren't produced until 1954, shortly before the U.S. developed more easily weaponized solid-fuel hydrogen bombs.)

Still, one might ask again why the U.S. tried to keep it secret, and from whom. The thing is, keeping it secret from the USSR just wasn't an option: when you set off 10 megatons in the Pacific Ocean, people are going to notice. Now, it's true that the Soviets later claimed that they botched their fallout monitoring program at that stage of things (and thus apparently were unable to analyze the MIKE fallout to the degree that would have revealed fundamental design information, thus saving Soviet dignity when they came up with the same idea independently!),2 but it's clear that they were aware that something big had happened in the Pacific Ocean. And the only thing that big would have been an H-bomb.

When your nuclear test involves vaporizing an entire island, it's a bit hard to keep it secret.

The secrecy of the H-bomb has long been an interest of mine, because it was instituted so early (Truman put the AEC under a "gag" on discussing H-bomb topics in 1950, which they struggled to get reversed), and persisted for a relatively long time (the US didn't officially admit to having H-bombs until 1954, after the Castle BRAVO accident) despite the weighty subject matter. Information on the Ivy Mike shot wasn't released until nearly two years after it was detonated, which is a long time to try and keep something that big secret!

Who were they trying to keep it from? Well, everybody. The timing and circumstances of MIKE were not politically ideal. It was detonated just days before the 1952 Presidential election, and there was considerable question to whether it should be delayed until after the election took place. In the end it was decided that delaying it would be a politically tricky thing, so they just went ahead with it when they were ready. Truman didn't make it a political issue, though he easily could have. When President-elect Eisenhower was briefed on it, he was relieved that the AEC hadn't told anybody, because he didn't want to tip off the Russians to anything whatsoever.3 All that was immediately let out was a terse statement that admitted that the test series "the test program included experiments contributing to thermonuclear weapons research" — the same thing they had said after Operation Greenhouse. From that point until the Operation Castle debacle it just never seemed like the right time to say anything.

Of course, as I said, you can't really keep something that large truly secret. And indeed — Ivy MIKE leaked almost immediately. Thus we turn to this week's document, a series of AEC correspondence by Morris Salisbury, their public relations officer, Gordon Dean, the Chairman of the Atomic Energy Commission, and J. Edgar Hoover, infamous head of the FBI.4

Click for PDF.

Only a few hours after the first H-bomb detonation, the AEC public relations man got a call from someone at the Department of Defense who had got off the phone with Clay Blair, Jr., at Life magazine wanting to confirm that the US had indeed just detonated a hydrogen bomb. Just prior to that, they had gotten another phone call from Time magazine:

Hobbing [Time]: Is this the big day?
Thompson [AEC]: Why don't you tell me? What are you talking about?
Hobbing: We understand that the H-bomb has just been set off.
Thompson: We have a standard policy of no comment about weapons tests. We haven't anything to say in that field.
Hobbing: Aren't you getting out a release, don't you usually issue releases after you have made a shot?
Thompson: We have at times issued releases or statements after a shot in Nevada. We have never followed such procedure on tests at Eniwetok.
Hobbing: Don't you have any releases coming out there this afternoon?
Thompson: I don't know offhand. I'll have to check.
Hobbing: I mean about H-bombs.
Thompson: No.

A not entirely compelling performance on behalf of the AEC representative, there. Dean opted to have the FBI try and track down the source of the leak — the exact place and time of the shot was considered extremely sensitive information (because it would help the Soviets reconstruct information from the fallout), and the fact that it involved an H-bomb at all meant that it was "restricted data" (the unauthorized dissemination of which could even carry the death penalty).

Over the course of the week the story made its way into the press — and the AEC's secrecy on the issue itself became a main part of the story.

Los Angeles Times, November 7, 1952 — The story starts to rear its head (center page).

"The United States may be keeping secret an explosion of the world's first full-scale hydrogen bomb." (L.A. Times, November 7, 1952)

Los Angeles Times, November 9, 1952

" 'No Comment' was the only reply from the commission to inquiries based on an H-bomb story story in a Los Angeles newspaper today." (L.A. Times, November 9, 1952)

Finally the AEC release the terse statement I mentioned earlier, which, when paired with the rumors, and several "first-hand accounts" made the H-bomb test a fairly "open secret."

New York Times, November 17, 1952

It's still worth wondering, why try to keep it so secret? I mean, as we've seen from the film (released later), Operation Ivy was no small affair. (Interestingly, and this was news to me, an Air Force pilot actually died while taking fallout samples. Not from the radiation, mind you, but because he ran out of fuel and crashed the plane.5 This is the only acute, immediate death I've ever heard of during a U.S. nuclear test. Are there more?) Over 2,500 people were present at the test site, and the bomb itself was pretty conspicuous. As far as I know, nobody was ever charged with "leaking" the news about the MIKE shot.

A short version is to say that by this point, the AEC was taking all of its guidance on public releases relating to the H-bomb from the National Security Council, who saw no benefit to transparency. There's more to this story, but we'll leave it at that for now.

A few parting observations:

  • In all of the news coverage, notice that it is the AEC who gets the blame for the secrecy. This isn't exactly true — the "no comment on the H-bomb" policy had been decided before the shot by the National Security Council, and the post-shot silence was dictated by both Truman and Eisenhower. But the very secrecy of the matter obscures the source of the secrecy.
  • In a sense, one could see the U.S. as participating in a form of "strategic opacity" regarding its possession or non-possession of a hydrogen bomb between 1952 and 1954. Like Israel today, the U.S. then derived some advantage from its vagueness — if everyone "knew" that the U.S. had an H-bomb, but the U.S. didn't announce it, it could help avoid troublesome international issues (like criticism from allied countries who decried the H-bomb effort) while also avoiding several acute strategic weaknesses (like the fact that their "H-bomb" was not yet really a deliverable military weapon).
  • On the other hand, the H-bomb issue as a whole was one of the real turning points with respects to the AEC and the press. It was in the 1950s that the AEC's relationship with the press soured in a bad way, and when it got its most fearsome reputation as an agent of censorship and an enemy of disclosure. Some of this was deserved, but some of this was not. As pointed out, a lot of that secrecy didn't derive from the AEC at all, but other sources of power it was beholden to.

Ultimately, like so much regarding the hydrogen bomb (more on this in a future post), one has to wonder what it all added up to. The AEC was already in a pretty prime strategic relationship with regards to the arms race, and it didn't have any great reason to assume otherwise. I don't think it got them very much to be secretive, but I do think it hurt them. Then again, it wasn't entirely up to them what was secret and what wasn't — a case of "gambling with other people's money," or, more correctly, "gambling with other agency's reputations," on behalf of the NSC.


  1. Note that it was November 1 local, Eniwetok time — in the U.S. itself it was Halloween, which I find appropriate. []
  2. See Hugh Gusterson, “Death of the authors of death: Prestige and creativity among nuclear weapons scientists,” in Mario Biagioli and Peter Galison, eds., Scientific authorship: Credit and intellectual property in science (New York: Routledge, 2003), 281-307, riffing off of the account in David Holloway's Stalin and the Bomb. []
  3. Richard G. Hewlett and Jack M. Holl, Atoms for Peace and War, 1953-1961 (Berkeley: University of California, Berkeley, 1989), 3-4. []
  4. Roy B. Snapp, "Note by the Secretary – Letter to J. Edgar Hoover, Operation Ivy, AEC 483/33," (18 November 1952), copy in Nuclear Testing Archive, Las Vegas, NV, as document NV0409009. []
  5. Mark Wolverton, "Into the Mushroom Cloud," Air & Space (August 2009). []