DEFENSE DISCUSSION U.S. Army Gen. Martin E. Dempsey, chairman of the Joint Chiefs of Staff, and Air Chief Marshal Mark Binskin, chief of Australia's defense force, meet with their staffs on Australian navy base HMAS Watson in Sydney, Feb. 23, 2015. SHARE: Download: Full Size (0.07 MB) Credit: VIRIN: 948516-E-IDN43-137.jpg Photo Gallery