As long as some of us choose to rely on nuclear weapons, we continue to risk that these same weapons will become increasingly attractive to others.

America is always a good target for a populist. In many countries, particularly authoritarian systems, if you want to get an extra bonus, you bash the Americans.

Barack Obama has injected fresh momentum into efforts - stalled for a decade - to bring about nuclear disarmament.

The Muslim Brotherhood is a religiously conservative group. They are a minority in Egypt. They are not a majority of the Egyptian people, but they have a lot of credibility because all the other liberal parties have been smothered for 30 years.

We know North Korea has the plutonium that can go into the bomb.

Egyptian President Mohammed Morsi grabbed full power for himself. Not even the pharaohs had so much authority, to say nothing of his predecessor Hosni Mubarak. This is a catastrophe - it a mockery of the revolution that brought him to power and an act that leads one to fear the worst.

The Egyptians have grown in confidence, theyve tasted freedom, and theres no way back.