Even if not a single new country was "allowed" (sovereignty, where art thou?) to use nuclear, the majority of all power could still be nuclear. Pretty much all South American countries of note use nuclear, add to this Europe, Russia, China and the US, and that's what, 3/4 of all people in the world live in nuclear power nations? 90 % of all GDP is produced in these countries?

Peak oil is not an energy crisis. It is a liquid fuel crisis.