On December 1, 2016, President-elect Donald Trump announced that General James Mattis, former US CENTCOM, would be nominated to serve as United States Secretary of Defense in the coming administration. Foreign Media were quick to pick up on the nickname « Mad Dog ». It seems he is more than that. See what his former PAO (back when he was Commander general of the US Marine Corps) learnt from him about Real Leadership.
You can also read the original (written in milspeak) CG Staff Guidance (pdf).
Gretel C. Kovach, a San Diego journalist who specializes in USMC, pointed out in 2013 (the year he resigned from the Corps) that James Mattis also goes by the nicknames of « Chaos » (his callsign) and « Warrior Monk ». But the press prefers Mad Dog…