> Building fusion reactors wouldn't impact nuclear proliferation at all. I really can't think of a single fusion reactor design that produces "nuclear weapons m

> Building fusion reactors wouldn't impact nuclear proliferation at all. I really can't think of a single fusion reactor design that produces "nuclear weapons material." Since a fusion reactor would produce an intense neutron field, it doesn't take a genius to figure out that if you line the reactor vessel with natural uranium, you have a device for producing plutonium. That is by no means a showstopper, but it means fusion plants will need 24/7 security, IAEA inspections, worries when/if suspicious tinpot dictator states decide that they will need their own fusion power plants, etc. etc. Even if we'd magically solve the technical challenges in fusion, we won't be seeing things like dinky fusion-powered ships sailing around the oceans (for larger ships, one could envision some kind of IAEA monitoring system for those). Of course, if someone figures out aneutronic fusion (pB11 or such), these proliferation concerns would evaporate. That's a pretty big if, though. > dealing with extremely toxic metals. Spent fuel, in particular, is certainly radiotoxic, but chemically, no, not that big of a worry. Society routinely deals with other toxic heavy metals like lead as well, not to mention all kinds of other extremely toxic compounds.