Putin is behaving in a very dangerous way. And Donald Trump sounds as though he would simply sit back and allow that to go on. I worry about where that would end up.

I think it's a mistake to rely too much on any one economic factor. It's why investors try to spread their portfolio round.

Donald Trump seems to be unconcerned about the Russian aggression in Ukraine. By doing this he tells them that they can go ahead and do what they are doing. That is dangerous.

Iraq has no history of ethnic conflict.

Look, I think the notion that theres a dogma or doctrine of foreign policy that gives you a textbook recipe for how to react to all situations is really nonsense.

We did not go to war in Afghanistan or in Iraq to, quote, 'impose democracy.' We went to war in both places because we saw those regimes as a threat to the United States.

The use of force to liberate people is very different from the use of force to suppress or control them, or even to defeat them.