Radiation isn't as bad as most people think. The blast kills the most people, not the fallout. Sure, some people do get radiation sickness, but if you look at an annual cancer graph for Hiroshima in WW2, cancer only rose by a little.
The fear of the unknown is probably one of the greatest fears of all. Humans can't smell, feel, hear or see radiation, because we also can't stop it harming us 100%, this scares people.
Plus, the hydrogen bomb, is way greater than a nuclear warhead. If anything should be developed as a WMD in the future, it should be them. There will be a cure for cancer in the near future, with technology on the rise, I can see nukes becoming redundant in 60 years or so.
I'm no expert, just stating my opinion, but in the future, nuclear technology will only be used for energy- and even that will be replaced because of the waste it leaves behind.