Ranking Terrorist Threats By Degree Of Separation

This past year has been one of the FBI's busiest — at least when it comes to terrorism cases. In the first 10 months of 2009, there have been possible plots exposed in Denver; Springfield, Ill.; Dallas; Boston; and, just this week, Chicago.

With so many alleged plots, it's difficult to know how seriously to take any particular threat. So the intelligence community has an informal system for ranking them. The basic idea: The closer the link to al-Qaida, the more serious the plot.

Consider the case of Najibullah Zazi, the Denver-area shuttle bus driver who stands accused of plotting to blow up targets in New York City. Intelligence officials claim that the Zazi case is the most serious this country has faced since Sept. 11, 2001, because they believe Zazi had a direct link to senior al-Qaida leaders. Officials say that in addition to allegedly training in an al-Qaida camp, Zazi apparently called someone in Pakistan for instructions just before he was arrested.

That's seen as a red flag, because it suggests that al-Qaida was behind the plot in some way. And al-Qaida, as a general matter, likes its attacks to be big.

"In my view, these tend to be the most serious [cases], because of course, the goal of them is to create a terrorist spectacular," says Bruce Hoffman, a Georgetown professor who advises the U.S. government on terrorism. "They are looking to stage an enormous attack that will, as 9/11 did, change the game or change the calculation."

That's the highest-level category — a plot connected directly to al-Qaida.

The Second Level

Plots backed by other terrorist groups with links to al-Qaida are seen as the second most serious level of terrorist threat. These groups are essentially affiliates of al-Qaida. That, experts say, makes them only slightly less dangerous.

"I think how we understand al-Qaida and how we categorize different affiliations with al-Qaida is actually very important — and changing," says Karen Greenberg, the executive director of the Center on Law and Security at New York University.

She says a growing number of terrorist groups now identify with al-Qaida and then, in turn, train their own recruits for terrorist operations.

What worries intelligence officials is that, increasingly, these affiliate groups are training people from the United States. The alleged terrorist plot uncovered in Chicago this week fits into this second category.

Prosecutors arrested two Chicago men they said were plotting a terrorist attack overseas. According to the complaint, the men wanted to attack a Danish newspaper that had published controversial cartoons depicting the Prophet Muhammad in 2005.

What got the attention of U.S. intelligence officials was that one of the Chicago men allegedly trained with a Pakistani terrorist group called Lashkar-e-Taiba, which has ties to al-Qaida. The group was behind the attacks on Mumbai, India, nearly a year ago.

Level Three

The third category of plot usually involves angry young men, who are often radicalized on the Internet. They get into chat rooms, meet like-minded people, and then begin dreaming up their own plots.

Hosam Smadi, a Jordanian teenager living in Texas, allegedly drove a truck full of what he thought were explosives into the underground garage of a skyscraper in Dallas earlier this month. He allegedly told FBI undercover agents that he wanted to blow up the building because he was a supporter of Osama bin Laden.

The agents first discovered Smadi in a chat room. As the investigation proceeded, they posed as al-Qaida operators and furnished him with fake explosives. He was arrested after he dialed a cell phone number he thought would detonate the bomb.

Then there's the Boston man also arrested earlier this month and accused of planning an attack on a U.S. shopping mall. In this case, Tarek Mehanna trolled the Internet, visited jihadi chat rooms and decided to travel to Yemen in search of terrorist training.

Mehanna didn't manage to get into any of the camps. Frustrated, he allegedly came back to Boston and decided to lash out on his own.

As it turns out, prosecutors say, he couldn't get the automatic weapons he wanted for a mall attack, either. Mehanna reportedly asked a local gang member for help getting weapons, but the gang member apparently refused to help him.

According to Vahid Brown, a fellow at West Point's Combating Terrorism Center, these kinds of plots tend to be much less lethal. "These have not proven to be people who are able to do much damage," he says. "So I think it is appropriate to consider them as being much less dangerous than groups or cells or operational units who are closely connected to al-Qaida central."

Finding The Connections

Sam Rascoff used to work the intelligence desk at the New York Police Department. He says that ranking plots based on how closely they are connected to al-Qaida or its affiliate groups is a good first step toward understanding them. But that's only the beginning.

"Part of what you do when you do counterterrorism is not to think about just this case, but the run of cases that are currently going on or may go on in the future," Rascoff says. Rascoff says law enforcement has to figure out why people in this country turn to violent jihad in the first place — and why the number of homegrown plots is growing at such an alarming rate.