This is for a plutonium bomb. So, where would a bunch of people who are having difficulty refining uranium get plutonium? It’s a fairly short list, actually. The bad news is that the North Koreans are on it. The good news is that they haven’t solved this one yet either. But other people have, and that knowledge will be out there...for a price.
After years od delay the Russians are set to start up Iran’s Busheir Nuclear power plant - the fuel was delivered and stored months ago.
The various reports I’ve seen indicate that once operating this facility has the capacity to spin of enough plutonium for upwards of 12 medium sized weapons be year
Likewise ans you noted, I believe it’s likely the North Koreans have sold Iran lots of goodies