SECDEF
PETERSON AIR FORCE BASE, Colo. -- Secretary of Defense Dr. Robert M. Gates is greeted by Col. Stephen N. Whiting (right), 21st Space Wing commander, and Gen. C. Robert Kehler, Air Force Space Command commander, on the Peterson flightline April 1. Secretary Gates made a brief stop at Peterson while traveling to the U.S. Air Force Academy. Secretary Gates is the Nation’s 22nd secretary of defense and has served in this position since Dec. 18, 2006. He is the only secretary of defense in U.S. history to be asked to remain in that office by a newly elected president. (U.S. Air Force photo/Craig Denton)