The Buzz

North Korea Might Just Blow Up a Nuclear Weapon in the Atmosphere

In October 1966, the Chinese conducted a nuclear test involving the ballistic-missile delivery of the warhead to their Lop Nur test site. This test was CHIC-4, held on 27 October. The missile was a CSS-1 medium-range missile, which flew about 900 kilometres before the warhead—a simple fission design with a yield of approximately 12 kilotons—was detonated in the atmosphere. CHIC-3 had a yield of 250 kilotons, and CHIC-5 300 kilotons, so it’s reasonable to conclude that the Chinese also made an effort to dial back the CHIC-4 yield as a safety precaution. (As a point of interest, the CHIC-4 design—labelled ‘early, [and] inefficient’ by the CIA—is the one the Chinese later shared with the Pakistanis.)

Given that the US and Russia have both conducted end-to-end tests by using SLBMs, Kim Jong-un might be drawn to pursue a similar option. An SLBM needn’t involve overflight of Japan. And it would allow the test to be conducted remote from major urban areas. But that assumes, of course, that Kim has a working SLBM, not to mention a submarine capable of launching it—which he probably doesn’t at this point in time. What Kim has is an under-tested ICBM capability, plus of course an under-tested intermediate-range ballistic missile capability. If he decides to try for an end-to-end nuclear test with one of those, we might be in trouble.

None of the previous tests by the US, Russia and China, remember, have involved an intercontinental-range or even an intermediate-range missile. Any scenario in which Pyongyang attempts such a test—humorously labelled ‘Juche Bird’ by some—is fraught with danger. Indeed, even the preparations for such a test, including the loading of a nuclear warhead onto a long-range missile, might well trigger a US pre-emptive strike. After all, how could a US president be confident that a nuclear-tipped ICBM was being launched only for testing purposes?

This first appeared in ASPI's The Strategist here