http://www.truth-out.org/news/item/38620-james-mattis-is-a-war-criminal-i-experienced-his-attack-on-fallujah-firsthand
Tuesday, December 06, 2016
By Dahr Jamail, Truthout | News Analysis
...During the April 2004 siege, more than 700 civilians were killed by the US military, according to Iraqi doctors in the city whom I interviewed in the aftermath of that attack.

While reporting from inside Fallujah during that siege, I personally witnessed women, children, elderly people and ambulances being targeted by US snipers under Mattis' command. Needless to say, all of these are war crimes.

During the November siege of Fallujah later that same year, which I also covered first-hand, more than 5,000 Iraqi civilians were killed. Most were buried in mass graves in the aftermath of the siege.

Also...
Brutes in Suits: Male Sensibility in America, 1890–1920 By John Pettegrew
https://books.google.com/books?id=QT8N-ib2C-IC&pg=PA332&lpg=PA332&dq=mattis+fallujah+white+phosphorus pp. 331-332