[Nathan Zachary]

I was under the impression that U235 isn’t the only nuclear material that nukes can be made from, that other types and grades can and do make fine nuclear bombs.

[Mr. Quarterpanel]

There are only really 2 types of Nuclear weapons: Uranium and Plutonium.
Uranium bombs are big, heavy, require well over 100 pounds of U235 enriched to 90-95%, have relatively low yields (20 kilotons) and are highly radioactive. On the plus side they are very simple in design, and pretty much guaranteed to work every time.

Plutonium bombs, on the other hand, can be made very small, light, and boosted yields can be up to 100 kilotons. The downside is that they are very complicated, and require sophisticated shaped charges and nanosecond timing to detonate properly. North Korea demonstrated how hard this type of weapon is to get right, by messing it up.

[Rembrandt_fan]

I’m sure there’s any number of ways a non-hydrogen nuke can be produced not limited to U-235. I’m no scientist, so I can’t presume to hold forth on the engineering or theoretical aspects. If the Iranians are indeed making their own bomb and not purchasing a device via corrupt, amoral Russian scientists or insane North Korean dictators, what we would need to do is find out the details of the data supplied to the Iranians by the Khan network. The best way to do that, of course, is to interrogate Khan himself, but I don’t think the Pakistanis, who hold him in custody, are keen to help.