The future source of energy is something all countries are faced with and as many have pointed out the realistic future is nuclear.
This brings about another question which is how can we justify banning countries from using nuclear power when it is the only solution to a world wide problem.
Who is going to dictate to the "unfriendly" nations and how many armed conflicts are we prepared to get involved in to prevent others acquiring the technology.
Threats are not going to be the solution as that can only lead to more conflict and loss of life .

There is a better way but it doesn't pay as well as warmongering.