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395358 01: Military Police from the 229th National Guard unit of Virginia Beach patrol the Ronald Reagan Washington National Airport October 4, 2001 in Arlington, Virginia. The airport reopened with tighter security after being closed since the September 11 terrorist attacks. (Photo by Joe Raedle/Getty Images)

395358 01: Military Police from the 229th National Guard unit of Virginia Beach patrol the Ronald Reagan Washington National Airport October 4, 2001 in Arlington, Virginia. The airport reopened with tighter security after being closed since the September 11 terrorist attacks. (Photo by Joe Raedle/Getty Images)