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Second question: Michael Fletcher from the Washington Post, Why would Iran or North Korea listen to the US & Russia regarding nukes?

Give us a chance as 2 nuclear superpowers, tell the world about the dangers of nuclear proliferation.

There are countries that have decided not to pursue nuclear weapons, Brazil, South Africa, Libya

Part of the goal here is to show the US and Russia are going to fulfill their commitments and other countries feel its an international effort

Rebuild a non proliferation framework that works for all countries. Establish international norms that can be verified and enforced. Not about singeling out Iran and North Korea, expecting everyone to abide.