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395358 05: Rocky, a bomb sniffing K-9 officer, patrols 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 05: Rocky, a bomb sniffing K-9 officer, patrols 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)