Homeland Security Secretary Janet Napolitano, accompanied by Transportation Security Administration chief John Pistole, announces the expansion of a passenger pre-screening initiative on Feb. 8, 2012, at Washington's Ronald Reagan National Airport. (Associated Press)

Photo by: Charles Dharapak

Homeland Security Secretary Janet Napolitano, accompanied by Transportation Security Administration chief John Pistole, announces the expansion of a passenger pre-screening initiative on Feb. 8, 2012, at Washington's Ronald Reagan National Airport. (Associated Press)