Secretary Gates listens to a briefing. Secretary of Defense Robert M. Gates (left) listens to a briefing about how U.S. soldiers use unmanned ground vehicles to find an enemy during a room clearance demonstration at the future combat systems facility at Fort Bliss, Texas, on May 1, 2008. SHARE: Download: Full Size (0.07 MB) Credit: VIRIN: 132855-M-HPU98-602.jpg Photo Gallery