Leader's Greeting Defense Secretary Jim Mattis talks with Air Force Gen. Lori Robinson, commander of U.S. Northern Command, after arriving at Peterson Air Force Base, Colo., Nov. 16, 2017. DoD photo by Army Sgt. Amber I. Smith SHARE IMAGE: Download Image: Full Size (1.34 MB) Tags: Travels , JIm Mattis, SecDef, Northcom, Northern Command, AIR FORCE, Airmen Photo By: Amber I. Smith VIRIN: 171116-D-SV709-0049B.JPG Photo Gallery