**FILE**Transportation Security Administration's Behavior Detection Officer Terrence McClain (right) watches United Airlines passengers checking in for the morning flight at Washington's Ronald Reagan Washington National Airport on April 8, 2010. (Associated Press)

Photo by: Manuel Balce Ceneta

**FILE**Transportation Security Administration's Behavior Detection Officer Terrence McClain (right) watches United Airlines passengers checking in for the morning flight at Washington's Ronald Reagan Washington National Airport on April 8, 2010. (Associated Press)