having to buy the radioactive materials from dictatorships
Not really, but also kinda. The biggest exporters of ore are Kazakhstan, Namibia, Canada, and Australia.
The only major producers that aren't American puppets stripping themselves of resources to maintain western hegemony are Russia, Niger, China, and India, who total less than 15%.
I wouldn't call Russia or India not-dictatorships, but I don't see them using US weapons and training to put down a restive population and keep the resources and money flowing out like Kazakstan.