140121-F-JW079-217 Secretary of the Air Force Deborah Lee James listens as 1st Lt. David Krigbaum, 90th Security Forces Tactical Response Force, explains the TRF mission of defending the nation’s nuclear assets against any hostile threat Jan. 21, 2014. James and Chief Master Sgt. of the Air Force James Cody, background, visited the 20th Air Force and 90th Missile Wing on F.E. Warren Air Force Base, Wyo., to learn about the Minuteman III weapon system and the Airmen who operate, maintain, secure and support it. (U.S. Air Force photo by R.J. Oriez)