Our security depends on having good relationships with our allies. Donald Trump mainly shows contempt for them.

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.

Islamic State is mainly a direct result of the failure in Syria. That's where IS has grown. That's where IS spread from.

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.

I told my father I had to try political science for a year. He thought I was throwing my life away.

It would be a huge mistake to abandon democracy promotion. Peaceful political change has been enormously successful in the past years in Eastern European countries as well as in countries like South Korea, South Africa, Chile and Indonesia. However, if possible, the use of force is something to avoid except in cases where genocide is threatened, like Bosnia or Libya or with regimes that threaten our security, like the Taliban and Saddam Hussein.

I mean, we're going to probably debate the Iraq war for at least as long as I'm alive.