How big Al Qaeda's footprint is in the US

Anyone who can tell you how many terror cells are operating in the United States can also tell you how many angels can dance on the head of a pin.

Or so says a former CIA operative.

But he and other intelligence experts say it's all but necessary to assume terror cells are here. And several revelations this week suggest that far more than prudence is at play. New reports indicate that an Al Qaeda operative captured in Pakistan had contacted people in the US as recently as this year.

There are also the disturbing details about the discovered case studies of the targeted buildings in Washington, New York, and Newark that prompted last weekend's heightened terror alerts. The English was perfect, probably written by someone who had lived in the United States for a long time and was professional and meticulous, according to reports. The studies were three and four years old, which indicates that whoever wrote them could be long-term resident.

The renewed concern about Al Qaeda's footprint in the US has coincided with several developments overseas. Security was tightened at Rome's main airport following threats directed at Italy. Pakistan, meanwhile, continued with a crackdown on Islamic militancy, and a dozen Al Qaeda suspects were arrested in Britain.

In all, the developments show an even stronger emphasis on tracking down Al Qaeda. But in the US, the challenge of identifying and finding individuals in sleeper cells can be daunting: Unlike many of the spies and moles of the cold-war days that frequented the cocktail circuit in Washington, Al Qaeda operatives in everyday America specialize in blending in there. Because of the cell structure of the organization - think of it as bubble wrap with no individual cell even knowing which others exist - it's clear how difficult gathering intelligence against this enemy is.

"At the risk of sounding paranoid, the best constructed terror cell and the best constructed spy cell is your next-door neighbor," says Ron Marks, a former CIA official. "The problem with James Bond is that he's way too flamboyant. I'd never have hired him."

That said, experts also note that the likelihood that someone's neighbor is an Al Qaeda operative is slim to none. While no one knows how many of Osama bin Laden's partners in terror are here, there are some estimates. In February 2003, FBI Director Robert Mueller testified before Congress that he believed there were several hundred individuals with ties to Al Qaeda living and operating in the US.

That indeed makes them needles in the haystack of a nation of 280 million people. While experts note that it's still important to report suspicious activity, they're also worried about fueling anti-Arab discrimination. Yet they say that through cooperation with that community, some of the best information can be gleaned.

"It's a really tough one. My first thought is the public is an irrelevant player," says Juliette Kayyem, an intelligence expert at Harvard's Kennedy School of Government. "The likelihood that I am going to figure out that the guys next door are terrorists is pretty unlikely. It's better to hope that the government is doing a good job of professional surveillance."

In fact, government officials announced Thursday that two leaders of a mosque in Albany, N.Y., were arrested on charges stemming from an alleged plot to purchase a shoulder-fired missile.

These arrests follow ones in Lackawanna, N.Y., and Portland, Ore. But experts say doubts remain about the seriousness of those individuals' connections to Islamic extremists. It's clear none had the ability to produce the kind of professional and detailed reports that prompted this week's heightened security alerts.

Critics calling for reform in the nation's intelligence services cite the revelation that those individuals who wrote the detailed reports may still be in the US - along with hundreds of others. "The fact that we've never been able to locate these people is a critique of our own intelligence and law-enforcement apparatus - it's in disarray," says Michael Greenberger, director of the University of Maryland's Center for Health and Homeland Security and a former Clinton adviser. "The question is, Why have these people never been picked up?"

But other intelligence experts note that one of the greatest conundrums of the intelligence business is that it can't brag about successes, and it has to own every failure. US officials have closed down several major fundraising operations believed to have terrorist ties. They've also worked successfully with intelligence agencies overseas in attacking Al Qaeda at its core. "We've had some major successes [overseas with Al Qaeda.] We've slain the dragon, but now we're dealing with room full of snakes," says Frank Cilluffo of George Washington University and a former security adviser to President Bush. "What you've seen now is the franchising of Al Qaeda. They're in England, Jordan, Spain, and there've been a number of arrests recently that bode well."

But the question remains, how many snakes are there in the US ... and can they be caught before they strike again.