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 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.

I can't imagine that I would be asked that by the president-elect [Donald Trump], or then-president [Barack Obama]. But it's - I'm very clear. I voted for the change that put the Army Field Manual in place as a member of Congress. I understand that law very, very quickly and am also deeply aware that any changes to that will come through Congress and the president.

I just hope we can find our way back to engaging with one another, arguing strongly with one another, and then going down and having a root beer together or something and - and having a good laugh about it as we work together for the best interests of the next generation of Americans who are going to inherit this country.

Ultimately, a real understanding of history means that we face NOTHING new under the sun.

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.

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.