Security Forum Marine Corps Gen. Joseph F. Dunford Jr., chairman of the Joint Chiefs of Staff, speaks while Michele Flournoy, former undersecretary of defense for policy, moderates at the Center for a New American Security's National Security Forum in Washington, D.C., Dec. 14, 2015. DoD photo by D. Myles Cullen SHARE: Download: Full Size (1.98 MB) Tags: Chairman, Center for a New American Security, Michele Flournoy, Joseph F. Dunford Jr., All images Credit: Myles Cullen VIRIN: 151214-D-VO565-003.JPG Photo Gallery