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No, we have not been ignoring the bubbling reports of possible North Korean nuclear tests in 2010. Nor have we been ignoring the speculation that there may have been an Iranian connection. But this is a classic cautionary tale. Much of what we “know” is really what we think we know about what someone else is speculating about research that has only just been released—literally days ago--and which has not been subjected to further scientific scrutiny. As we always say, caveat emptor.
Here are the basics; for those wanting even more detail, the SinoNK group has been extremely thorough and sensible about this.
The story emanates from three sources, which we will discuss not in chronological order but in the order that they stoked the current story. The first is a long piece in Die Welt am Sonntag (online) on March 4 titled “Iran soll Atombombe in Nordkorea getestet haben.” Right from the start, we have a problem; this passive construction can be translated inelegantly as “It is said that Iran has tested an atomic bomb in North Korea,” or less literally as “Iran allegedly tested an atomic bomb in North Korea.” But as we will see, it is the author of the piece--Dr. Hans Rühle—who has “said” or “alleged” this and it far from being established at all.
According to a short profile on the World Security Network, Rühle is appropriately credentialed: he headed the Planning Staff of the German Ministry of Defense, served as coordinator of the Federal Security Academy, and was general manager of NATO Multirole Combat Aircraft Development and Production Management Agency (NAMMA). In short, he has been a player in the German defense establishment, no doubt has high-level intelligence clearances, and has also published on nuclear proliferation.
However, it is our business to be skeptical of credentials and the piece either contains a whole series of classic logical fallacies or is based on sources that remain unseen.
The core claims are based on research done by Lars-Erik De Geer, currently on the staff of the Swedish Defense Research Agency, and first reported in a story by Geoff Brumfiel in Nature back in February. The full version of De Geer’s work—“ Radionuclide Evidence for Low-Yield Nuclear Testing in North Korea in April/May 2010”--did not even appear until the last couple of days. The venue is Science and Global Security, a reputable publication devoted to publication of scientific and technical studies relating to arms control, disarmament, and nonproliferation policy.
The short teaser piece at Nature is really what got the ball rolling. It tells the story of De Geer’s research. The Comprehensive Nuclear-Test-Ban Treaty has not been ratified by the major nuclear powers, but the Comprehensive Nuclear-Test-Ban Organization (CTBTO) supports a network of radio-isotope monitoring stations and serves as the hub for a group of scientists working on detection. Other stations not formally part of the network also participate.
At a meeting in August 2010, a group of scientists looked at the monitoring data from Russian and Japanese stations (Ussuriysk in Russia; Okinawa and Takasaki in Japan) and identified anomalies in the form of isotopes that are typically associated with nuclear activities (xenon-133 and 133m, barium-140 and its radioactive decay product lanthanum-140). De Geer picked up the ball and did further work with South Korean monitoring stations and meteorological data. He was also motivated by an odd story released by the KCNA on May 12, 2010--which we reproduce in full below—that claims that North Korea had succeed in “fusion.” De Geer’s careful analysis came to the conclusion that North Korea carried out two small-yield nuclear tests in April and May 2010 and with isotopic signatures that suggested—but could not definitively establish--an HEU device.
De Geer’s essay—as we noted, only a very late entrant into the discussion—is a highly technical piece on his findings based on analysis of the isotopes picked up by the Russian, South Korea and Japanese monitoring stations. Needless to say, the science in the piece is way over our heads, and the heads of most of the journalists that are covering the issue. However the article closes with a lengthy section called “Constructing a Scenario that Fits All Observations,” that is accessible to non-scientists and thus easy to seize on. Based on the nature and timing of the isotopes released, De Geer offers a story that involves a deep underground low-yield test in a chamber that provided an effective seal against the release of certain isotopes, but which was then subsequently opened releasing others.
But De Geer admits repeatedly that the scenario he traces out is speculative. There are numerous technical issues still to be addressed, including why seismic monitoring stations did not pick up the tests (inadequate yield? Failure?), why other isotopes typically related to testing were not released (underground tests in conditions which served to screen them?), and whether other nuclear events might have been responsible for the isotope signatures found. But that’s to be expected; it’s how science works. The Nature piece rightly cites some doubters.
Back to Rühle. First, it is not clear that Rühle was even privy to De Geer’s research or simply riffing off of the Nature piece; the Welt article suggests the latter. But Rühle stretches out on a speculation that De Geer makes virtually in passing: that the tests may speak not only to North Korea’s enrichment capabilities but also “disguised co-operation agreements with other states with nuclear ambitions,” with a footnote to Iran.
Here is where Rühle’s imagination comes into play. The two critical paragraphs are worth reproducing here in the original, with our translation (happily corrected).
"Woher also stammt das waffenfähige Uran für die beiden 2010 getesteten Sprengsätze? Hierfür gibt es nur zwei mögliche Erklärungen, die auch die strenge Geheimhaltung der Tests sinnvoll und notwendig erscheinen lassen. Zum einen könnte es sich um waffenfähiges Uran aus Nordkoreas eigener geheimer Produktion handeln.
…
Die zweite Erklärung wäre, dass Nordkorea einen nuklearen Fremdtest durchgeführt hat – in diesem Fall eines iranischen Sprengsatzes. Das wäre zwar eine Sensation, allerdings nicht völlig überraschend. Seit einigen Jahren registrieren die Geheimdienste eine enge Zusammenarbeit zwischen nordkoreanischen und iranischen Experten bei der Vorbereitung eines nuklearen Tests."
Our (loose) translation:
"So where did the weapons-grade uranium come from for the two 2010 tests? There are only two possible explanations that appear reasonable given the strict confidentiality of the tests (SH, ie., that the North Koreans sought to cover them up). On the one hand they could have involved weapons-grade uranium from North Korea's own secret production.
…
The second explanation is that North Korea conducted a test for a foreign power (Fremdtest), in this case, an Iranian explosive device. That would be a sensation, but not entirely surprising. For several years, intelligence has noted close cooperation between North Korean and Iranian experts in preparing for a nuclear test…"
Do we even need to bother dismantling this? Of course, he is right that the tests could have come from North Korean fissile material. But the leap of inference that there are only “two possible explanations” and that the second one is that they have tested an actual Iranian device is—to be polite—a bit fanciful. And remember, we have not even firmly established beyond doubt that there were two, one or any tests.
Rühle goes on to note the variety of reports out there on DPRK-Iran relations—which we have also tracked (most recently here). These have included allegations of collaboration in which Iran and North Korea are believed to have benefited from the others' testing of missiles, and possibly on the nuclear front as well. And there can be little doubt that if Iran had effectively tested, or even shared test results, it would constitute a major foreign policy challenge not only for the administration but for his critics. OK, tough guys; what now?
The atmosphere is getting a little testy around Iran at the moment—as the sparring around Prime Minister Netanyahu’s visit demonstrated—and the last thing we need is to stoke the fires on the basis of speculation with little or no basis in fact. We rule nothing out. But to date, many of the claims being made sound like classic argumentum ad ignorantiam: that the proposition is true because it has not yet been proven false.
Needless to say, we are going to be following this one very closely.
KCNA Story
DPRK Succeeds in Nuclear Fusion
Pyongyang, May 12 (KCNA) -- Scientists of the DPRK succeeded in nuclear fusion reaction on the significant occasion of the Day of the Sun this year, according to Rodong Sinmun Wednesday.
It goes on:
The successful nuclear fusion marks a great event that demonstrated the rapidly developing cutting-edge science and technology of the DPRK.
The nuclear fusion technology is called "artificial solar" technology as it represents a field of the latest science and technology for the development of new energy desired by humankind.
The nuclear fusion technology for obtaining safe and environment-friendly new energy the source of which is abundant draws great attention of world science at present.
Scientists of the DPRK have worked hard to develop nuclear fusion technology their own way.
They solved a great many scientific and technological problems entirely by their own efforts without the slightest hesitation and vacillation even under the conditions where everything was in short supply and there were a lot of difficulties, thus succeeding in nuclear fusion reaction at last.
In this course, Korean style thermo-nuclear reaction devices were designed and manufactured, basic researches into nuclear fusion reaction completed and strong scientific and technological forces built to perfect the thermo-nuclear technology by their own efforts.
The successful nuclear fusion in the DPRK made a definite breakthrough toward the development of new energy and opened up a new phase in the nation's development of the latest science and technology.
