If Al Qaeda or its allies carried out the bombings in London, as many investigators suspect, Islamic extremists would have succeeded in striking their top European target as terrorist networks are gaining combat experience and inspiration from the conflict in Iraq, officials said Thursday.
Experts said the attacks bore many signatures of the fragmented but virulent networks that have operational or ideological ties to Osama bin Laden’s organization: multiple targets, near-simultaneity, significant civilian casualties and political timing.
But the lack of details about the blasts prompted debate among experts about whether the plot was the work of a longtime cell based in Britain, recently arrived operatives from Iraq, or a combination of the two.
The bombs went off as President Bush sat down with Prime Minister Tony Blair and other world leaders at the Group of 8 summit in Scotland, a day after London was chosen to host the 2012 Summer Olympics.
The timing recalled the car bombings against British targets in Istanbul, Turkey, in 2003 as Bush met with Blair in London, as well as last year’s bombings of commuter trains in Madrid that killed 191 people three days before Spanish national elections.
Like Spain at the time of the Madrid bombings, Britain is a staunch ally in the U.S.-led coalition in Iraq. Britain had repeatedly been threatened by Al Qaeda, leading security chiefs to say an attack was inevitable.
Experts said Britain’s role in Iraq probably served as a strong motivation for the bombers, citing a message posted on a website declaring that Britain had paid the price for its presence there and that other members of the coalition faced the same fate.
Some investigators suspect the plot involved Islamic extremists from Europe who went to Iraq, gained combat experience and ideological fervor and then returned to wage their holy war.
Before Thursday’s attacks, investigators say, they had been concerned by the increasing presence in Europe of veterans of the Iraq conflict. During the last six months, Western intelligence reports described a “redeployment” onto the continent of operatives of Abu Musab Zarqawi, the leader of Al Qaeda in Iraq. The operatives were thought to be planning attacks, a senior European police official said.
A senior U.S. intelligence official cited indications that Zarqawi had moved to reestablish his network in Europe, where it had already been linked to past plots in Britain, France and Germany. In February, U.S. intelligence officials said they had intercepted a message from Bin Laden to Zarqawi, urging him to expand his focus beyond the Iraq insurgency. Bin Laden instructed Zarqawi to consider mounting attacks on targets in the United States.
“We know Zarqawi has in fact renewed efforts to try to expand his reach outside the Iraqi theater, to include the European homeland,” the senior intelligence official said.
He also described intelligence about Al Qaeda’s aspirations to carry out new attacks in Europe. Although the official said nothing was known about the ethnicity or citizenship of the plotters, he noted that the name of the group claiming responsibility for the London attacks, the Secret Organization of Al Qaeda in Europe, was similar to the name of the group in Iraq.
A British law enforcement official said Britain’s counter-terrorism agencies, which have been effective at infiltrating Islamic extremist groups at home, would find it more difficult to detect foreign fighters back from Iraq.
“I think it’s more likely to be returnees, perhaps people connected to the Zarqawi group,” said the British official, who requested anonymity. “It doesn’t feel like home-grown. Because we have got a pretty good feel for what’s going on among the groups in Britain. We have got good contacts in the Muslim community, and you would have thought at some point someone would have detected something. Unless it was a group that completely slipped in under the wire.”
But some investigators and experts favored another scenario involving local plotters. A British anti-terrorism official said returning fighters appear less well-organized and cohesive than networks that have developed in Britain.
“If we are talking about returning jihadis from Iraq, our knowledge of them and how they are structured does not necessarily fit with this operation,” the official said.
Experts said the bombings of a major transportation system required an extensive support network in Britain, which, unlike neighboring countries, still screens travelers from Western Europe at its borders, making it more difficult for would-be terrorists to slip into the country.
“My point of view is that it was not returnees from Iraq,” said Stefano Dambruoso, Italy’s judicial attache in Vienna and a veteran anti-terrorism prosecutor. “There was this desire to attack in London for a long time. It was just a question of time. When Al Qaeda says they are going to do something, eventually they do it.”
Experts say Bin Laden’s battered organization has evolved into a constellation of networks connected to the core command structure sometimes more by ideology than clandestine messengers or Internet communications.
Partly because Al Qaeda’s senior leadership has been degraded -- with Bin Laden and his senior deputies believed to be hiding along the Afghanistan-Pakistan border -- U.S. officials said the London bombings were probably not planned or controlled by the group’s leadership.
U.S. intelligence officials and counter-terrorism experts said Thursday’s violence demonstrated that terrorists remain capable of unleashing devastation nearly four years after Sept. 11, even in a country where security forces are vigilant and skilled.
Global surveillance did not detect any increase in communications, or “chatter,” among suspected extremists before Thursday’s attacks, U.S. officials said. Similarly, last year there was no increase in chatter hinting at the Madrid attacks, Spanish officials said.
On a day when Al Qaeda also claimed to have killed an Egyptian diplomat in Iraq, some counter-terrorism experts in the United States called for a reassessment of the progress against the network.
“I think we vastly overestimate the damage we have done to Al Qaeda,” said Michael Scheuer, a former senior counter-terrorism official at the CIA and a critic of Bush administration policy.
Dozens of Al Qaeda operatives have been killed or captured in the last four years, Scheuer said, but the network has survived by becoming increasingly decentralized and adopting new modes of communication.
Moreover, militants linked to Al Qaeda pulled off their first strikes ever in Western Europe last year with the Madrid bombings and November’s assassination of a Dutch filmmaker.
Many of the suspects in those cases were known to police as Islamic radicals and were under surveillance at the time of the attacks.
Officials say those cases revealed the rise in Europe of a new generation of young, inexperienced terrorists of predominantly Moroccan origin. Anger and propaganda about the Iraq conflict tended to drive their fanaticism, and few attended the clandestine training camps like those that produced thousands of religious warriors in Afghanistan until late 2001.
The London subway attacks bear a resemblance to the Madrid bombings, in which explosives were detonated by remote control on commuter trains.
The evidence suggests the Madrid bombing attacks were mainly a local plot inspired by Al Qaeda that may also have received technical expertise and limited direction from veteran militants, particularly operatives tied to the Zarqawi network operating in and around Iraq.
Some of the alleged ringleaders played a role in recruiting and dispatching aspiring holy warriors from Europe to Iraq, which may also have been at play in Thursday’s attacks.
Police in Britain have disrupted several plots that illustrate the multiethnic membership of extremist organizations that have made London their base since the 1990s. London mosques have served as the headquarters of leaders of Egyptian, North African, Persian Gulf and Pakistani movements.
London was the longtime home of cleric Abu Qatada, accused by Western security officials of acting as a top Al Qaeda ideologue who inspired Zarqawi and others.
A group of Britons of Pakistani descent were arrested last year for possessing explosives for alleged plots against civilians in shopping malls and other public places.
In 2002, British police investigated intelligence reports that extremists planned to bomb aboveground subway stations with vehicles packed with gasoline containers, but they were unable to substantiate the tips, the British law enforcement official said. British authorities have disrupted 20 plots in the last three years, experts said.
The London attacks required long-term planning, said Charles Heyman, a senior defense analyst at Jane’s Defense Consultancy, who talked with security officials in London after the attacks.
“We suspect there’s quite a bit of a home-grown element to this,” Heyman said. “The logistics, the planning, the reconnaissance -- the reconnaissance is absolutely vital in any operation like this. They may spend months until they actually get it right.... Somebody worked very hard at this one. It’s very, very well-planned.”
The plot also suggests the involvement of a large number of people, experts said.
“If we assume there were four bombs involved, you’re not talking about someone who just planted it, you’re talking about people who constructed the device, selected the target, briefed the bombers and coordinated the operation, and you’ve got to take into account that they were given some kind of safe housing while they were in London -- they may still be in London,” said Paul Wilkinson, an international relations professor at St. Andrews University, who chairs the advisory board for the school’s Center for the Study of Terrorism and Political Violence.
Wilkinson and other experts speculated that the attacks might have combined a local infrastructure with leaders or skilled operatives from outside Britain.
If networks involved in the Iraq violence played a role, that would be the worst-case scenario feared by Europe’s anti-terrorism services since the conflict in Iraq began attracting holy warriors from Europe. Extremists from Britain, France and other countries have died in suicide attacks in Iraq.
Over the last year, authorities have detected an increasing presence of insurgents back from the fighting in Iraq. The Dutch alone have identified “dozens” of such former combatants, a U.S. law enforcement official said.
Iraq could replace Russia’s Chechnya republic, Bosnia-Herzegovina and Afghanistan as the breeding ground for terrorists who could unleash their new experience, skills and fervor on the West, European officials say. The CIA issued a classified report in May warning that Iraq had become a more effective training ground than Afghanistan for terrorists, and that the threat would spread as foreign fighters left Iraq and returned to their home countries or migrated elsewhere.
Muslims flocking to Iraq from other countries are getting firsthand exposure to “a broad range of terrorist activity, everything from assassinations, kidnappings, bombings to attacks with conventional weapons,” said a U.S. intelligence official who described the contents of the classified report on condition of anonymity.
In contrast to the rustic training camps of Afghanistan, Iraq insurgents learn to operate and evade detection in an urban environment, the official said.
Iraq is breeding “a generation of people who have the potential to be the leadership of Islamic extremism for some time to come,” the intelligence official said.