The land of the flighty

[Lissa]

Hi,
You probably could. The advances in electronics and explosives since the days of the Manhattan Project are such that consumer grade materials now are better than the best they had to work with then. But, really, a gun type bomb (like the original uranium bomb) is very low tech. You're not going to fit a bunch of them on an ICBM MIRV bus, but a fifty foot private boat could carry one with no problem at all. As a matter of fact, the original was delivered by B29 (IIRC) that only needed to be slightly modified.

As to determining whether the test occurred at all and was successful, that's not so easy. Underground testing was developed precisely so that a minimum of radiation would be released to the outside, so that the heat and blast signature would be contained, and (when done right) so that seismographic monitoring of the shock waves would give a misleading indication of the yield. The idea then was not to let your enemies (at that time, the USSR and the USA, depending on where you sat) know that you'd conducted a test, much less how it worked out. So, either the Koreans pulled off a successful test using good underground test techniques, or they pulled off an unsuccessful test (and the techniques don't matter). And most of us will never know which.

--Pete

I'm betting it was a fizzle. As I noted above, getting the weapons grade material isn't too difficult if you have a pile and enough neutron flux to convert U238 to Pu239. The technology to make the detonators all detonate properly and at the same millisecond is the real crux on making a compressive bomb work. I'm not sure NK has the technology to actually make those.