The US still does a ton of nuclear energy and weapons research. Policy is generally made by the people doing the actual work - who influence politicians - than by the politicians themselves. We live in a high technology society, and make a lot of policy based on scientific R&D. There is plenty of populist rhetoric, but aside from that the Western world is largely run by scientists and technologists, for better or worse. Nuclear power will never not be on the table as long as humans have nuclear capabilities.