My understanding is that making nuclear weapons is not that hard, especially "gun type" bombs like the one dropped on Hiroshima. Of course, the latest generatio

My understanding is that making nuclear weapons is not that hard, especially "gun type" bombs like the one dropped on Hiroshima. Of course, the latest generation of thermonuclear bombs with their delivery mechanism and countermeasures are another story, but if all you want is "a nuclear bomb", you don't need all that. Getting the materials needed to make that bomb is the real hard part. You don't find plutonium cores and enriched uranium at the grocery store. You needs lots of uranium ore, and very expensive enrichment facilities, and if you want plutonium, a nuclear reactor. Even of they give you all the details, you won't have the resources unless you are a nation state. Maybe top billionaires like Elon Musk or Jeff Bezos could, but hiding the entire industrial complex and supply chain that it requires is kind of difficult.