Posts Tagged ‘Hydrogen bomb’

News and Notes

Rumbles from North Korea

Saturday, January 9th, 2016

This past week and this next week are the last of my winter break before the new semester starts, which in the true fashion of academia means I am more busy than I usually am trying to cram as much non-teaching “work” into every day as possible. North Korea’s test of a nuclear weapon earlier this week, of course, just added to the workload. Thanks, Kim Jong-un. I am behind on my annual Nuclear History Bibliography, but it is coming, soon. NUKEMAP usage has been about 10X higher than normal — over 300,000 users last week.

New Yorker - An H-bomb by Any Other Name

I have written up a piece for the New Yorker’s Elements blog on the historical-technical-political dimensions of calling something a “hydrogen bomb,” or disputing it, that went up yesterday. I also talked a bit to Business Insider about how the true “Teller-Ulam design” of a thermonuclear weapon is not merely a single bomb design but an entire system of designing a getting of possible effects — so one ought not necessarily be expecting the North Koreans to make something that looks like Ivy Mike, Castle Bravo, or, god forbid, the Tsar Bomba. The North Koreans themselves, in their official statement (a wild read in and of itself), claimed that the “technological specifications of the newly developed H-bomb for the purpose of test were accurate and scientifically verified the power of smaller H-bomb” — a lot of little qualifications that seem to be saying, “we’re trying for miniaturization, not high yields, and this was a scientific test of a principle, not of a full-yield warhead.”

Given their strategic situation, a smaller bomb would make a whole lot more sense than something the size of a school bus. And I would note that the tendency to test all weapons at full power (or even more than the projected yield) is something that, while characteristic of the American program, is not necessarily the only way to do things. (The Soviets typically tested large bombs at half-power, on purpose.)

The seismic waveform of the North Korean test.

The seismic waveform of the 2016 North Korean nuclear test, as detected by a station in Mudanjian, China. Click here to listen to it rendered as audio. Source: Incorporated Research Institutions for Seismology.

Which is just to say, I don’t think we (at least those of us in the unclassified world) quite have enough information to really parse out what the North Koreans were trying to do in that test. The yield estimates coming out — ranging from 6 to 30 kilotons or so — don’t sound like much, in and of themselves. But there’s still a lot we don’t know, and might not know.1

Somewhere in between hysterically overestimating North Korea’s capabilities and smugly underestimating them is some sort of middle ground, a place where we need to acknowledge that this is 60-year-old technology, and the sheer technical difficulty alone is probably not going to stop them from becoming a fully-fledged nuclear power.

  1. And there are also ways to reduce the seismic signature of nuclear tests — like setting off a test in the cavern created by a previous test. It isn’t clear what incentive North Korea would have in making their tests look smaller than they actually were, but, then again, there is much about their thinking that is not intuitive to those of us on the outside. So I’m not sure that’s a likely scenario, but I don’t think it can be ruled out as impossible. []
News and Notes | Redactions

H-bomb headaches

Friday, March 27th, 2015

Once again, the US government has gotten itself into a bad situation over the supposed secret of the hydrogen bomb. As The New York Times reported earlier this week, the Department of Energy (DOE) censors demanded that the physicist Ken Ford heavily redact a manuscript he had written on the history of the hydrogen bomb. Ford, however, declined to do so, and you can buy the unexpurgated text right now on Amazon in Kindle format, and in hardback and paperback fairly soon.

Ken Ford by Mark Makela for the New York Times.

Ken Ford by Mark Makela for the New York Times.

Ford was a young physicist working with John A. Wheeler during the 1950s, and so a lot of his book is a personal memoir. He is also (in full disclosure) the former head of the American Institute of Physics (my employer from 2011-2014), and I was happy to give him some assistance in the preparation of the manuscript, mainly in the form of tracking down declassified/unclassified sources relating to his story, and helped him get solid citations to them. Ken actually just recently came to Hoboken so we could iron out a few of the final citations in a Starbucks near my apartment. I knew he was having some issues with classification review, but I didn’t know he was going to play it like this — I am impressed by his boldness at just saying “no” to DOE.

Nothing I saw in his work struck me as anything actually still secret. Which is not to say that it might or might not be officially classified — just that the technical information is much the same kind of technical information you can find in other, unclassified sources, like the books of Richard Rhodes and Chuck Hansen, and people on the web like Carey Sublette, among others. And therein lies the rub: is information still a secret if it is officially classified, even if it is widely available?

This has been a tricky thing for the government to adjudicate over the years. The Atomic Energy Act of 1946 (and its revisions) charges the Atomic Energy Commission (AEC), and later the Department of Energy, with regulating “restricted data” wherever it appears, wherever it comes from. According to the law, they don’t have any choice in the matter. But over the years they changed their stance as to the best way to achieve this regulation.

One of the earliest decisions of the Lilienthal AEC was to adopt a “no comment” policy with regards to potentially sensitive information published by people unassociated with the nuclear weapons complex. Basically, if someone wanted to speculate on potentially classified topics — like the size of the US nuclear stockpile, or how nuclear weapons worked — the AEC in general would not try to get in their way. They might, behind the scenes, contact editors and publishers and make an appeal to decency and patriotism. (Sometimes this got expressed in a comical fashion: they would have “no comment” about one paragraph but not another.) But they generally did not try to use threat of prosecution as the means of achieving this end, because they felt, correctly, that censorship was too blunt an object to wield very effectively, and that telling someone on the outside of the government that they had hit upon classified information was tantamount to revealing a secret in and of itself.

Howard Morland then-and-now. On the left, Morland and his H-bomb model, as photographed for the Washington Post in 1981 (at the time his book account of the Progressive case, The Secret that Exploded, was published). At right, Morland and me at a party in Washington, DC, just before I moved to New York. He is wearing his H-bomb secret shirt he had made in 1979 (which he discusses in his book). I felt very honored both to see the original shirt and to see the pose he imagined he might do with it before the press, to reveal the secret to the world.

Howard Morland then and now. On the left, Morland and his H-bomb model, as photographed for the Washington Post in 1981 (at the time his book account of the Progressive case, The Secret that Exploded, was published). At right, Morland and me at a party in Washington, DC, just before I moved to New York. He is wearing his H-bomb secret shirt he had made in 1979 (which he discusses in his book). I felt very honored both to see the original shirt and to see the pose he imagined he might do with it before the press, to reveal the secret to the world.

There were a few instances, however, where this “no comment” policy broke down. The best-known one is the case of United States v. Progressive, Inc. in 1979. This is the famous case in which the DOE attempted to obtain (and was briefly granted) prior restraint against the publication of a magazine that claimed to contain the “secret of the hydrogen bomb,” written by the journalist/activist Howard Morland. The DOE convinced a judge to grant a restriction on publication initially, but in the appeals process it became increasingly clear that the government’s case was on fairly shaky grounds. They declared the case moot when the researcher Chuck Hansen had a paper on hydrogen bomb design published in a student newspaper — in this case, it looked like an obvious attempt to back out before getting a bad ruling. Morland’s article appeared in print soon after and became the “standard” depiction of how the Teller-Ulam design works, apparently validated by the government’s interest in the case.

In this case, the issue was about the most egregious incursion of the Atomic Energy Act into the public sphere: the question of whether the government could regulate information that it did not itself play a part in creating. The “restricted data” clause of the Atomic Energy Act (after which this blog is named) specifies that all nuclear weapons-related information is to be considered classified unless explicitly declassified, and makes no distinction about whether said information was created in a laboratory by a government scientist or anywhere else in the world by private citizens. Thus nuclear weapons information is “born secret” according to the law (unlike any other forms of controlled national defense information), which in cases like that of The Progressive puts it in direct conflict with the First Amendment.

Ford’s book is something different, however. Ford was himself a government scientist and had a security clearance. This means he was privy to information that was most definitely classified as both “restricted data” and national defense information. He worked on Project Matterhorn B at Princeton, which was part of the hydrogen bomb effort in the early 1950s. He signed contracts that governed his behavior, both while working for the government and later. He agreed to let the government evaluate his work for classified information, and agreed he would not give away any classified information.

At left, the redacted Bethe article as published in Scientific American, April 1950. At right, the original draft, redacted by the Atomic Energy Commission (photograph taken by me at the National Archives, College Park).

At left, the redacted Bethe article as published in Scientific American, April 1950. At right, the original draft, redacted by the Atomic Energy Commission (photograph taken by me at the National Archives, College Park).

There is a historical parallel here, and a better one than the Progressive case. In 1950, the magazine Scientific American ran a series of articles about the hydrogen bomb. The first of these was by the gadfly physicist Louis Ridenour. Ridenour had no connection with nuclear weapons work and he could say whatever he wanted. But the second was by Hans Bethe, who was intimately involved with classified nuclear work. Bethe obviously didn’t try to publish anything he thought was secret. But the AEC got several passages deleted from the article anyway.

The passages removed were extremely banal. For example, Bethe said that it seemed like they would need to use the deuterium-tritium reaction to achieve fusion. This level of basic information was already in the Ridenour article that was published a month before. So why delete it from the Bethe article? Well, because Bethe was connected with the government. If Ridenour says, “tritium is necessary,” it doesn’t mean that much, because Ridenour doesn’t have access to secrets. If Bethe says it, it could be potentially understood by an adversary to mean that the deuterium-deuterium reaction isn’t good enough (and it isn’t), and thus that the Los Alamos scientists had found no easy short-cut to the H-bomb. So the same exact words coming out of different mouths had different meanings, because coming out of Bethe’s mouth they were a statement about secret government research, and out of Ridenour’s mouth they were not. The whole thing became a major publicity coup for Scientific American, of course, because there is no better publicity for a news organization than a heavy-handed censorship attempt.

I have looked over a lot of Ford’s book. It’s available on Amazon as a e-book, or as a PDF directly from the publisher. I haven’t had time to read the entire thing in detail yet, so this is nothing like a formal review. The sections that I imagine drew the ire of the DOE concern some of the early thinking about how the Teller-Ulam design came about. This is an area where there is still a lot of historical ambiguity, because tracing the origins of a complex technical idea is not straightforward even without classification mucking things up. (I am working on a paper of this myself, and have a somewhat different interpretation than Ken, but that is really neither here nor there.)

Ken Ford Building the H-bomb

There’s nothing that looks classified in Ken’s work on this to me. There are references to things that generally don’t show up in government publications, like “equilibrium conditions,” but the existence of these kinds of technical issues are common in the open literature on thermonuclear weapons, and a lot of them are present in the related field of inertial confinement fusion, which was largely declassified in the late 1990s.1

So why is the DOE pent up over Ford? It is probably not an issue of the content so much as the fact that he is the one talking about it. It is one thing for an unaffiliated, uncleared person like me to say the words “equilibrium conditions” and talk about radiation implosion and tampers and cryogenic cooling of plutonium and things of that nature. It’s another for a former weapons physicist to say it.

It’s also related to the fact that because Ken was a former weapons physicist, they have to review his work. And they have to review it against their official guides that tell them what is technically secret and what is not. And what is allowed by the DOE to talk about is not the same thing about what people on the outside of the DOE do talk about. So, for example, this is pretty much most of what the DOE considers kosher about thermonuclear weapons:

  • The fact that in thermonuclear (TN) weapons, a fission “primary” is used to trigger a TN reaction in thermonuclear fuel referred to as a “secondary.” 
  • The fact that, in thermonuclear weapons, radiation from a fission explosive can be contained and used to transfer energy to compress and ignite a physically separate component containing thermonuclear fuel.  Note: Any elaboration of this statement will be classified.
  • Fact that fissile and/or fissionable materials are present in some secondaries, material unidentified, location unspecified, use unspecified, and weapons undesignated. 

Now you can find a lot more elaboration on these statements in the works of Chuck Hansen, Carey Sublette, and, hell, even Wikipedia these days. (Fun fact: Howard Morland, of The Progressive case, is an active Wikipedian and contributor to that page.) And in fact there is a lot that has been released by the government that does lend towards “elaboration” of these statements, because it is impossible to full compartmentalize all of this kind of information in such neat little boxes.

But the job of the DOE reviewer was to sit down with the guide, sit down with Ken’s book, and decide what the guide said they had to do regarding the book. And in this case, it was about 10% of the book that the guide said they had to get rid of. And in this case, they are bound by the guide. Now, at a certain point, one has to say, if the guide is saying that lots of stuff that is already in Richard Rhodes’ Dark Sun, published 20 years ago, still needs to be kept under lock and key, well, maybe the guide needs to be changed. But there is arguably something of a difference between Rhodes (an outsider) writing things, and Ford (an insider) writing the same things. But it’s hard to see how any of this is going to matter with regard to national security today or in the future — it doesn’t seem like these kinds of statements are going to be what enables or disables future proliferators from acquiring thermonuclear weapons.

"How institutions appear / how institutions are." From one of my favorite comics published on Subnormality, by Winston Rowntree.

“How institutions appear / how institutions are.” From one of my favorite comics published on Subnormality, by Winston Rowntree. In this analogy, Ken is the beaver.

What’s amazing, again, is not that the DOE told Ken to delete things from his book. That is somewhat expected given how the classification system works. What’s amazing is that Ken told them to shove off and published it anyway. That doesn’t happen so often, that a once-insider won’t play ball. And it has no doubt put the DOE in a tough situation: they’ve set things up for a good story (like the one in the New York Times) about the silliness of government secrecy, and as a result have probably resulted in a lot of book sales that wouldn’t have otherwise happened. In this case, their attempt at preserving some form of secrecy has certainly resulted in them just calling more attention to the work in question.

What can they do to Ken? Well, technically, they probably could prosecute him under the Atomic Energy Act, or potentially the Espionage Act. But I’m pretty sure they won’t. It would be a public relations nightmare for them, would probably result in the release of even more information they deem sensitive, and Ken is no rogue agent. Which just goes to highlight one of the points I always make when I talk to people about secrecy: from the outside, it can look like government institutions are powerful and omnipotent with regards to classification. But they are usually weaker and more frail than they appear, because those who are bound by secrecy usually end up losing the public relations war, because they aren’t allowed to participate as fully as those who are on the outside.

  1. The Teller-Ulam design is perhaps better called the Equilibrium Super, to distinguish it from the Non-Equilibrium “Classical” Super design. In a basic sense, it refers to the fact that they were trying to achieve conditions that would result in a lot of fusion all at once, as opposed to a traveling “wave” of fusion along a cylinder of fuel. []