It's hard to conceive that it would take more forces to provide stability in post-Saddam Iraq than it would take to conduct the war itself and secure the surrender of Saddam's security forces and his army. Hard to imagine.

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

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

For the private sector to flourish, special privilege must give way to equal opportunity and equal risk for all.

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.

One of the things that ultimately led me to leave mathematics and go into political science was thinking I could prevent nuclear war.

I don't know of a single instance of these Arab freedom fighters holding up pictures of bin Laden. I know many instances of them displaying American flags in Benghazi or painting 'Facebook' on their foreheads in Cairo. The idea of freedom . . . is absolutely contradictory to what bin Laden stood for, which was . . . taking Muslims back to some medieval theocracy and encouraging people to die not for freedom but to go to paradise and to kill innocent people along the way. The contrast is really striking.