DEFENSE COOPERATION U.S. Navy Adm. Mike Mullen, chairman of the Joint Chiefs of Staff, speaks with Japanese Defense Minister Toshimi Kitazawa in Tokyo, Dec. 9, 2010. Mullen traveled to Japan to discuss how to better leverage its military expertise and improve defense cooperation in light of North Korean aggression. SHARE: Download: Full Size (0.06 MB) Credit: VIRIN: 135162-L-KNJ44-767.jpg Photo Gallery