In his new book, The Terror Factory: Inside the FBI's Manufactured War on Terrorism, investigative journalist Trevor Aaronson analyzes 10 years of terrorism cases that were prosecuted in the United States after Sept. 11.

By assembling a database of the cases and going through court records, he concluded that the FBI, which receives $3 billion per year for counterterrorism, is "the organization responsible for more terrorist plots over the last decade than any other."

Rather than stopping actual terrorist attacks, like the Boston bombing, the FBI focuses significant resources on using informants and sting operations to entrap would-be Islamic terrorists who "never could have obtained the capability to carry out their planned violent acts were it not for the FBI's assistance," he writes in his book.

Aaronson, the co-director of the Florida Center for Investigative Reporting, spoke to CBC News by phone from Florida.

Trevor Aaronson: What the database looked at was a little more than 500 defendants who'd been prosecuted on international terrorism charges in the decade after 9/11. Of the 500 cases, you could expel about half of them as being not specifically related to terrorism. These were cases where someone was charged with immigration violations, or lying to the FBI and that the federal government alleged that they had some sort of connection to terrorism, however tangential that might have been. But none of those cases involved people who were specifically been engaged in a plot of any kind.

And then, of the 250 or so that are left, you can really only point to five or so cases that involved someone who posed a significant threat, that was dangerous on their own, like Faisal Shahzad, for example, who delivered a car bomb to Times Square in 2010 that, fortunately, didn't go off. Or Najibullah Zazi, who came close to attacking the New York subway system, or the shoe bomber and the underwear bomber. But really, roughly those five cases are the ones of the 500 that you can point to and say, "those were dangerous guys."

By contrast, there were about 150 defendants who were caught in terrorism sting operations.

In these sting operations the FBI provided everything that these men needed. They provided the weapons, the transportation and in some cases even the idea itself. These 150 defendants were people that the FBI alleged could one day, possibly, be terrorists. And these sting operations were meant to pre-empt them from becoming terrorists.

I argue in my book, in all of these cases, the evidence suggests that these men became terrorists only because the FBI provided them with the capability. These were incompetent men who were only capable of the most minor crimes.

The people that are caught in these terrorism sting operations are Muslims who are living on the fringes of those communities. In many cases they are mentally ill. In other cases that are economically desperate, they're poor and the informant offers them inducements, such as money, assets. For example, an informant in a case outside New York City offered one man $250,000 and to buy him a barbershop if he moved forward in a plot. In other cases you have people who are really just losers in life, don't have many friends.

The informant has an incentive to find people who can be targeted in these sting operations, because they can make thousands of dollars in these operations. At the same time, then they are targeting people who are easily manipulated and easily brought in to these sting operations.

But in these cases, it's the informant and the FBI that are providing the means, providing the weapons. Left to their own devices these men are unlikely to have ever been able to acquire these weapons.

That's right. But the difference between Tamerlan Tsarnaev and the men caught in sting operations is the men caught in sting operations often are these loudmouths who never have the ability to go and make the bomb themselves, or are really more talk than action. So these FBI sting operations are able to easily draw out these people who are on the fringes of these communities saying kind of loudly, "I want to get involved in terrorism."

Instead, the Tamerlan Tsarnaevs and the Faisal Shahzads, Nidal Hassans, they're going undetected by the FBI because they're not stupid enough to go out and start talking to people about these kinds of things. That's the primary difference.

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