In Japan and South Korea there is deepening concern over the reliability of long-time American security guarantees – whether the U.S. will come to their aid in the event of a war. This has been turbo-charged by Donald Trump’s tough treatment of traditional U.S. allies, which has some in Tokyo and Seoul calling for a reassessment of their non-nuclear policies.
Eh. There’s nothing too crazy about developing from scratch. The hard part is generating your first batch of enriched uranium. A physics grad student could probably design a basic nuke. The US actually ran a test to that effect decades ago; a couple of physicists with no specialization in the nuclear side of things, and using only publicly available material, were able to design an implosion-type device. The expert consensus was that it would have worked just fine.
To get the uranium for the first bomb, you can always do what Israel did - have your spies literally steal it from US nuclear facilities.
Buying the blueprints would still remove the need for extensive testing, but you make a good point. After I posted the comment, I actually wondered about how hard it would be since there is so much information about nukes publicly available.
If you donated some money strategically you could probably get a copy of the US nuclear secrets to accidentally fall out of Mar-a-Lago’s bathroom window.