Old Guard Re-enlistment Defense Secretary Jim Mattis members of the 3rd U.S. Infantry Regiment , known as the Old Guard, during a ceremony at Joint Base Myer-Henderson Hall, Va., Sept. 20, 2017. DoD photo by Air Force Tech. Sgt. Brigitte N. Brantley SHARE IMAGE: Download Image: Full Size (1.43 MB) Tags: JIm Mattis, Soldiers, Army, SecDef, Northcom, Northern Command Photo By: Brigitte N. Brantley VIRIN: 170920-D-GO396-0687X.JPG Photo Gallery