Secretary of State Hillary Clinton conducts a briefing on the Nuclear Posture Review. Secretary of State Hillary Clinton conducts a briefing on the Nuclear Posture Review with Secretary of Defense Robert M. Gates, Chairman of the Joint Chiefs of Staff Adm. Mike Mullen and Secretary of Energy Steven Chu in the Pentagon on April 6, 2010. SHARE: Download: Full Size (0.05 MB) Credit: VIRIN: 349266-T-XAX58-509.jpg Photo Gallery