Airman 1st Class Sandra Crawford watches the Bagram Airfield perimeter from Tower 59 Feb. 16, 2012, at Bagram Airfield, Afghanistan. Perimeter response team members watch the Bagram Airfield perimeter for any potential threats and actively respond to all possible situations. Crawford is a PRT member with the 455th Expeditionary Security Forces Squadron. (U.S. Air Force photo/Airman 1st Class Ericka Engblom)