WASHINGTON—Perhaps the biggest surprise about Thursday's deadly attacks in London is that they didn't happen sooner.
London, one of the world's most cosmopolitan cities, is home to an array of Islamic dissidents, peaceful and otherwise, and with terrorism continuing unabated elsewhere in the world, Great Britain has long been high on the target list for al-Qaida and related groups because of its government's staunch support for the U.S. war in Iraq.
Sir John Stevens, Britain's top police officer at the time, put it this way in March 2004: "There is an inevitability that some sort of attack will get through."
Thursday's bombings of three subway trains and a double-decker bus at rush hour illustrate one of the great frustrations of the war on terror: It's nearly impossible to defend against assailants who use relatively simple technology to shock and disrupt civilian life, U.S. officials and counterterrorism experts say.
"These attacks are a grim warning that the threat of terrorism remains all too real, that groups like al-Qaida are willing to attack civilians without reservation and that even the most experienced anti-terrorist force cannot provide security in open democratic societies," security expert Anthony Cordesman of the Washington-based Center for Strategic and International Studies said in a statement.
While al-Qaida's core organization—sometimes known as "al-Qaida central"—has been on the run since the Sept. 11, 2001, attacks and stands denuded of much of its leadership, local groups inspired by it have popped up across the Middle East, North Africa and Europe.
Britain has long experience with terrorism from its three-decade battle with the Irish Republican Army, and its security services have disrupted several alleged plots by Muslim radicals over the last year and a half.
There were no definitive answers Thursday as to who was behind the string of London bombings.
But officials and experts agreed that it bore the calling card of groups associated with, or inspired by, Osama bin Laden's al-Qaida network.
A previously unknown group, calling itself the "Secret Organization of al-Qaida in Europe," claimed responsibility in an Internet posting and warned Denmark and Italy to withdraw their troops from Iraq. The claim couldn't be immediately verified.
A similarly named group, al-Qaida in Europe, claimed responsibility after the March 11, 2004, Madrid commuter train bombings, which killed 191 people.
Stephen Ulph, an Islamic affairs analyst for British-based Jane's Information Group, said the style and language of the letter on the Internet were similar to that of previous al-Qaida announcements.
This was "probably a propaganda attack. ...To say `we're still here,'" Ulph said by phone from his office in central London, a few blocks from one of the bombings.
The attacks overshadowed the Group of Eight summit hosted by British Prime Minister Tony Blair and attended by President Bush several hundred miles away in Gleneagles, Scotland.
But Ulph, who's affiliated with the Washington-based Jamestown Foundation, said the attacks were a failure strategically. "No great panic ... was caused by this," he said.
Later Thursday, U.S. government officials said there was growing consensus that all or most of the bombs weren't carried out by suicide attackers, but involved devices presumably timed or remote-controlled.
Beginning in 2003 and intensifying after the attacks on the Madrid commuter rail system, Londoners have been told repeatedly to prepare for similar attacks in their hometown. Again and again, the London Underground train system was described as "vulnerable."
London emergency workers held practice runs on how to respond to a terrorist attack on the subway. During the exercises, stretches of the Underground would be shut down, as police cadets pretended to be victims of an attack.
Police have broken up several plots. Last April, British security forces derailed a plot to flood sections of the subway with poison gas, or a so-called radioactive "dirty bomb." Police discovered a plan to release osmium tetroxide within the confines of the subway system, which officials said could have resulted in many deaths. Information on the alleged planned attack seemed to indicate a possible al-Qaida link.
Last August, British authorities also uncovered an alleged plot to set off a radioactive dirty bomb in London; they charged eight men with terrorism-related crimes.
One of them was Dhiren Barot, al-Qaida's reputed leader in Britain, who was alleged to have surveillance plans of buildings in New York, New Jersey and Washington that were the subject of a U.S. terror alert nearly a year ago.
London is also home to the Finsbury Park Mosque, where alleged Sept. 11 plotter Zacarias Moussaoui and "shoe bomber" Richard Reid worshipped. A radical cleric who used to preach there, Abu Hamza al-Masri, is on trial on 15 terrorism charges.
Stephen Gale, a counterterrorism expert at the Philadelphia-based Foreign Policy Research Institute, said London has "probably the largest concentration of al-Qaida sympathizers and cells in Western Europe."
But as to the attackers, Gale said, "Right now, we have no idea. And that's part of the problem. It's all ambiguous."
(Knight Ridder Newspapers correspondents Matthew Schofield in London and Jonathan S. Landay in Washington contributed to this report.)
(c) 2005, Knight Ridder/Tribune Information Services.
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