SECURITY DISCUSSION Defense Secretary Robert M. Gates, right, and U.S. Navy Adm. Mike Mullen, chairman of the Joint Chiefs of Staff, meet for bilateral security discussions with Armenian Prime Minister Serzh Sargsyan, left, in the Pentagon, Oct. 18, 2007. SHARE: Download: Full Size (0.03 MB) Credit: VIRIN: 115822-N-PVY09-697.jpg Photo Gallery