WASHINGTON—For three decades, commercial airliners have been terrorist bombers' target of choice.
Thursday's alleged foiled liquid-explosives plot in Great Britain was a vivid reminder that despite all the increased aviation security since the Sept. 11, 2001, attacks, blowing one or more of the giant silver birds from the sky remains one of the surest ways to sow horror among millions.
The shutting down of Heathrow Airport outside London and the cancellation of flights in scores of world capitals showed that even when a plot is blocked, its revelation can cause havoc for days by disrupting travel plans—and raising the specter of future attacks.
"Airplanes captured the imagination of the terrorists both for symbolic and operational reasons," said Brian Jenkins, a RAND research-center analyst and author of a new book on combating terrorism. "They were symbols of nations and symbols of national policy when other targets were heavily guarded."
Terrorists of various political stripes attacked passengers and commandeered planes through much of the 1970s. For six days in the summer of 1976, terrorists held 258 Air France passengers hostage on a runway in Entebbe, Uganda, before Israeli commandos freed them in a nighttime raid.
The first large-scale bombing of a commercial aircraft occurred June 23, 1985, when a bomb exploded on an Air India plane bound for New Delhi, plunging the plane into the Atlantic Ocean and killing all 329 passengers.
On Dec. 21, 1988, a Libyan man backed by his government planted a bomb that blew up Pan Am Flight 103 over Lockerbie, Scotland, as it traveled from London to New York, killing 270 people.
The Sept. 11 attacks combined the air piracy of an earlier era with the Air India and Pan Am bombings by turning four hijacked jetliners into missiles, crashing them into the World Trade Center, the Pentagon and a Pennsylvania field.
The alleged foiled plot that British authorities described recalled an earlier one that law-enforcement and intelligence officials also interrupted before it could be carried out.
In a mission code-named Operation Bojinka, radical Muslims tied to Osama bin Laden planned the virtually simultaneous bombings of 11 jetliners en route to the United States in January 1995. Their idea was to pack nitroglycerine into Casio watches to make "microbombs" and blow the planes from the air.
The perpetrators of the Lockerbie bombing used a barometric detonator to set off a bomb hidden in a radio-cassette player.
In another foiled plot after Sept. 11, fellow passengers prevented Richard Reid, a British Muslim convert, from setting his shoes on fire to detonate explosives concealed inside them on an American Airlines flight from Miami to Paris.
Charles Pena, a senior fellow at George Washington University's homeland security institute, said the idea of attacking planes still appealed to terrorists because a successful bombing most likely killed a large number of people, grabbed world headlines and airwaves, and had the ripple effect of crippling the travel industry and causing other economic harm.
With some previous bombing methods blocked by security measures that have been installed since Sept. 11, Pena said, the alleged planners of the United Kingdom plot are suspected of turning to liquid explosives.
"Terrorists always go after the weak link," he said. "They saw this potential weak link in the aviation system. They're going to continue to look for potential weaknesses in aircraft security, but not to the exclusion of other targets they might be interested in attacking."
(c) 2006, McClatchy-Tribune Information Services.
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