We are going to have to continue to keep the pressure on the enemy. There is no room for complacency on this.

It is mostly a matter of wills. Whose will is going to break first? Ours or the enemy's?

Fight with a happy heart and strong spirit.

We do everything humanly possible, consistent with military necessity, taking many chances to avoid civilian casualties, at all costs.

Since 9/11 we've been engaged in wars around the world, and General [James] Mattis has been a leading battlefield commander in many of those theaters, including in the April 2004 siege of Fallujah, where the US Marines killed so many people that the municipal soccer stadium in the city had to be turned into a graveyard for the dead.

I think the core problem is much closer to recognizing where force is of value, where it is useful, and to distinguish that from situations in which war is not useful or is indeed counterproductive.

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.