D.B. Cooper reached celebrity level fame for his 1971 hijacking of a Northwest Orient flight to Seattle. Threatening that he had a bomb, he extorted $200,000 (and four parachutes) from the U.S. government. Cooper's caper set off a rash of copycat hijackings for money in the next few years. Increasingly, hijackers also sought to use hijacking to bargain for political gain.
Although there were more hijackings in the United States than elsewhere, and international hijackings occurred in several regions, Palestinian guerrilla groups (as they were known in the 1970s) became associated with hijacking and international terororism. The Popular Front for the Liberation of Palestine successfully bargained for a prisoner exchange with the Israeli government following their 1968 hijacking of an Israeli El Al Flight. In response, El Al installed a baggage check program to ensure that every piece of baggage could be accounted for by a passenger.
In 1969 and 1970, even more spectacular hijackings of international flights by the PFLP took place. The hijacking by the PFLP of an American aircraft led to the first innovation in airport security in the United States: placing unidentified air marshals on flights. In 1970, President Nixon inaugurated the Federal Air Marshals program.
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