Adm. Mike Mullen joined Secretary Gates in a Pentagon press conference. Chairman of the Joint Chiefs of Staff Adm. Mike Mullen joined Secretary of Defense Robert M. Gates in a Pentagon press conference to discuss the resignation of Gen. Stanley A. McChrystal on June 24, 2010. McChrystal had been the senior commander of U.S. and NATO forces in Afghanistan. SHARE IMAGE: Download Image: Full Size (0.06 MB) Photo By: VIRIN: 693723-P-UZA69-144.jpg Photo Gallery