The first time you blow someone away is not an insignificant event.

ISIS is a threat to all civilized nations. America's intention is that the foreign fighters do not survive the fight to return home to North Africa, to Europe, to America, to Asia, to Africa. We're not going to allow them to do so. We're going to stop them there and take apart the caliphate.

I think, broadly speaking, the US military's role - US military activism in various parts of the Islamic world over the past several decades has been counterproductive.

You cannot allow any of your people to avoid the brutal facts. If they start living in a dream world, it's going to be bad.

We've backed off in good faith to try and give you a chance to straighten this problem out. But I am going to beg with you for a minute. I'm going to plead with you, do not cross us. Because if you do, the survivors will write about what we do here for 10,000 years.

The most important six inches on the battlefield is between your ears.

Be polite, be professional, but have a plan to kill everyone you meet.