What is the concern with proliferation?
The concern stems from the possibility of rogue nations or terrorists having access to nuclear materials that can be used for bombs. In the US, government policy on reprocessing of nuclear waste was reversed in 1977 during the Carter Administration for this reason. Other countries are reprocessing however — despite US policy. The international safeguards to prevent proliferation from recycling nuclear waste appear to be working well. Countries which are attempting to develop their own nuclear capability are generating their own plutonium.