The revelation of the arrest in October of Colleen Renee LaRose, who had adopted the pathetically predictable nom de guerre Jihad Jane, once again focuses national attention on homegrown terrorism.
But while worrisome, this threat needs to be kept in perspective. When you look at the data, and the history of terrorism, the picture is decidedly mixed.
Here's what we know:
From Sept. 11, 2001, to the end of 2009, there were 45 cases of domestic terrorism. That doesn't mean actual attacks. These include cases where American citizens or residents plotted to carry out terrorist attacks here; plotted here to carry out terrorist attacks abroad; were accused of providing material support to foreign terrorist organizations; or left the U.S. to join jihadist organizations in Afghanistan, Pakistan or Somalia.
In 2009, there were 13 cases, an increase from the average of about four cases a year from 2002 to 2008, there was an average of about four cases a year. There was also a marked increase in the number of individuals involved in 2009.
But while 45 cases might seem significant, keep in mind an average of only three people were accused in each case—and half the cases involved just a single person. In all, 116 individuals have been indicted since 2002, plus some missing Somalis who may have left the country to join fighters in Somalia.
And only two of the events, both occurring in 2009, resulted in fatalities: a soldier at an Army recruiting office in Arkansas, and the 13 people killed by Army Major Nidal Hassan at Fort Hood, Texas. Significantly, both involved lone gunmen who had decided to kill – a difficult-to-detect and all-too-common occurrence in the United States that often has nothing to do with terrorism.
Also important is the fact that, for the most part, these individuals recruited themselves into the role of terrorists in response to jihadist propaganda or events in the world. Many of them began their journey on the Internet, which has seen a significant increase in English-language jihadist Web sites and chat rooms.
And most of the plots could be described as more aspirational than operational. The would-be terrorists contemplated attacks on easy targets: shopping malls, subways and commuter trains, synagogues, federal and commercial buildings, banks, Army recruiting centers and other facilities. Some considered assassinating prominent U.S. politicians. Probably not all of the interrupted plots, if undiscovered, would have matured into actual terrorist attacks.
Keep in mind, too, what hasn't happened since 9/11. There's been no sustained jihadist terrorist campaign in the United States. The local Muslim community has rejected overwhelmingly its appeals and has actively intervened to dissuade those with more radical tendencies from violence. Domestic intelligence efforts have been expanded and improved and, thus far, have succeeded in thwarting all but two attacks. This has contributed to a deterrent effect.
It's also worth noting that America has seen far worse when it comes to domestic terrorism. In fact, the volume of terrorist activity was far greater in the 1970s, which saw 60 to 70 incidents, mostly bombings, on U.S. soil each year. Terrorists hijacked airliners; held hostages in Washington, New York, Chicago and San Francisco; bombed embassies, corporate headquarters and government buildings; robbed banks; murdered diplomats; and blew up power transformers, causing widespread blackouts.
These weren't one-off affairs but sustained campaigns by terrorist gangs that avoided capture for years.
Today's American jihadists plot deadlier schemes, but fortunately they lack the connectivity and capability to sustain the terrorist campaigns of the 1970s. What authorities now confront are tiny but potentially still lethal conspiracies, lone gunmen and a growing gallery of Jihad Janes and Jihad Joes.
This should not permit complacency. One competent operative, or a couple of would-be warriors who receive training abroad and return, can change the landscape and our perceptions.
Brian Michael Jenkins, author of Will Terrorists Go Nuclear? (Prometheus, 2008), is senior adviser to the president of the RAND Corporation, a nonprofit institution that helps improve policy and decision-making through research and analysis. His previous op-ed for AOL News was "How a Decade of Terror Changed America."
This commentary originally appeared on AOL News on March 12, 2010.