A crew member of a C-17 Globemaster III aircraft gives water to passengers on a Hurricane Gustav evacuation flight Aug. 31, 2008, at Louis Armstrong International Airport in New Orleans. The 2012 defense authorization bill gives the secretary of defense the authority to mobilize Air Force reservists to help U.S. communities affected by natural disasters. (U.S. Air Force photo/Staff Sgt. Shawn Weismiller)