Does a hydrogen bomb have a larger blast radius than an atomic bomb?

Answer 1

Trick question. The answer is vastly simplified--perhaps to the point of inaccuracy.

Having worked on a system that carried either payload, I can tell you that a hydrogen device will produce a larger blast radius with less long term radiation than the same physically sized uranium or plutonium device, but that efficient detonation does not occur until above the 50 kiloton range--not much of an issue when the average size of the devices of the five NPT states is taken into account. Much of the radiation released by a hydrogen reaction is in the form of heat, hence the term thermo-nuclear. All hydrogen bombs are fusion bombs. Solely uranium and plutonium bombs are fission devices. The difference is in the reaction (fission splits the atom, fusion compresses two hydrogen atoms into a helium atom--similar to the mechanism of stars). Additionally, all hydrogen bombs also have a fissile component that is used to compress and initiate the fusion reaction.