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

In a country with millions of people & cars going everywhere, the enemy is going to get a car bomb out there once in a while.

I'm from the American West. We have forest fires out there. And some of the worst forest fires in our history, the most damage were caused when we pulled the fire crews off the line too early. And so we're going to have to continue to keep the pressure on the enemy - ISIS. There's no room for complacency on this.

What concerned me was that [James Mattis] played not only a critical role as a battlefield commander in Fallujah, but also, afterwards, when he was promoted to various other higher-ranking positions, he served as a convening authority in court-martial proceedings against various marines who had been accused of atrocities - for example, in the Haditha massacre, where a group of marines went on a killing spree after one in their unit was killed.

If in order to kill the enemy you have to kill an innocent, don't take the shot. Don't create more enemies than you take out by some immoral act.

I don't see lethality as the problem. I mean, the lethality of US forces is quite remarkable.

I find it disturbing that no member of the Senate Armed Services Committee is willing to acknowledge that record of failure and to ask our next secretary of defense what he proposes to do to amend that sorry record.