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They think nuclear weapons are something that are only dealt with by high policy, and thus have no marketable third-party entry point. Such was my perception, anyway. I think it's kind of amazing.
All of the other social goods they want to accomplish involve immensely complex, emergent social problems that are probably intractable without massive reorganization. Whereas nuclear policy can be solved with laws, policy, etc. (And presumably less sexy as a result.)
