Sharing a Laugh Defense Secretary Jim Mattis shares a laugh with Mexican Secretary of National Defense Gen. Salvador Cienfuegos Zepeda during an armed forces parade in Mexico City, Sept. 15, 2017. DoD photo by Air Force Staff Sgt. Jette Carr SHARE IMAGE: Download Image: Full Size (0.6 MB) Tags: Travels , JIm Mattis, SecDef, Northcom, Northern Command Photo By: Jette Carr VIRIN: 170915-D-GY869-249A.JPG Photo Gallery