U.S. Air Force Staff Sgt. Martin L. Waller, foreground, and Senior Airman Jennifer M. Goulet, both of the 119th Security Forces Squadron, take a defensive posture during a simulated intruder exercise at a missile field security forces training site at the Minot Air Force Base, Minot, N.D. Aug.3. (U.S. Air Force photo by Senior Master Sgt. David H. Lipp) (Released)