Mattis Meets Defense Secretary Jim Mattis meets with members of the Joint Chiefs of Staff at the Pentagon Jan. 23, 2017. DoD photo by Air Force Tech. Sgt. Brigitte N. Brantley SHARE IMAGE: Download Image: Full Size (0.85 MB) Tags: Secretary of Defense , james mattis, Department of Defense, SecDef, Pentagon Photo By: Tech. Sgt. Brigitte N. Brantley VIRIN: 170123-D-GO396-0016.JPG Photo Gallery