Yes, the process involves production of Pu-239, which is weapon-grade and may raise proliferation concerns. But for the US, or France, or UK, or India, or China (and a bunch of others) this should not be a concern, since they officially have nuclear weapons.
It's mostly the political will, and the public opinion (which are interlinked) that limit a nuclear renaissance. If you talk about subsidies, please remember how huge were the subsidies that kickstarted the current solar and wind booms; early panels and wind towers were completely uneconomical by today's standards, and R&D costs were colossal. But now, with the technology streamlined and the economies of scale kicking in, solar is competitive even without subsidies.
The same could happen to a new crop of nuclear technology, much cleaner and more efficient than the kind we've inherited from 1970s.