A new study by Charles Kurzman, published in the Triangle Center on Terrorism and Homeland Security, declares terrorism by Muslim Americans “a minuscule threat to public safety.” The study showed that after a sudden spike in 2009, terror attacks by Muslim-Americans have declined steadily over the last three years. Of about 14,000 murders in the United States last year, not a single one resulted from Islamic extremism, said Mr. Kurzman, a professor of sociology at the University of North Carolina.
From this chart we can see the recent three year drop both in terrorist acts and terrorist plots:
Note that the bulk of the chart--the blue bars--is not actual terrorist acts, but terrorist "plots disrupted early." It seems that most terrorist plots hatched by Muslim Americans are caught early, a few (the red bars) are caught late, and between about zero and three happen each year. Exactly one was carried out in 2012, with the rest disrupted early. In all, 13 terrorist plots by Muslim Americans have come to fruition since 9/11, with one each in 2010, 2011 and 2012, none of which involved any fatalities.
The data around terrorist plots bounces around a fair amount. There is a much cleared decline since 9/11 when we look at the total number of suspects and perpetrators by year. Kurzman explains:
The number of Muslim-Americans indicted for support of terrorism -- financing, false statements, and other connections with terrorist plots and organizations -- fell even more dramatically than terrorist plots, from 27 individuals in 2010 to 8 in 2011 and 6 in 2012, bringing the total to 467 since 9/11 (Figure 5).
The internal numbers are somewhat unstable, but there's a definite decline in support for terrorism since 9/11 driven by the ominous category of "Link to Terrorism Not Made Public." 2001 and 2003 stand out there, with 9/11 in the former and the Iraq War in the latter. There's a peculiar odd-number trend, which may reflect some sort of two year cycle, the lack of U.S. elections in those years, or just random noise. (Random noise is a theme I'll be returning to shortly).
We also see the same drop in terrorist plots per Muslim-American citizen, which shows that the drop isn't from terrorists moving overseas.
Europe shows a steady decline in convictions of Muslims in terrorist plots, and a similar, if less precise trend for arrests. The U.S. line, while appearing more volatile, may help shed some light on a previous question: what's with the spike in 2009? We see a general downward trend, with arrests in 2001 and 2003 actually higher than in 2009 despite the spike. The big drop in 2008 provides a possible explanation for the 2009 spike in terrorist plots: random variance. Average those two years, and they fit the overall trend. It's possible there were actual reasons that terrorists waited until 2009, but it's just as likely that more attacks happened to fall in the calendar years of 2007 and 2009, and almost none in 2008.
Muslim-American terrorism dropped for the third year in a row, resulting in no injuries or fatalities in 2012. Fourteen Muslim-Americans were indicted for plotting terrorist violence, and another six were indicted for support of terrorism. Almost all of the plots became known to law enforcement at an early stage, before weapons or explosives were gathered.
As for why this is happening, Kurzman offers up a number of possibilities, while making no particular case for any of them: increased counterterrorism efforts, less desire to be terrorists or simple random variance.
Whatever the case, it seems clear that Muslim-Americans are no particular threat, and that it's past time for any post 9/11 hysteria to die down. There are real threats to Americans: heart disease, car accidents, gang violence, and more, but Muslim-American terrorists don't even make the top 100.
ALL IMAGES FROM: Muslim American Terrorism: Declining Further by Charles Kurzman, published in the Triangle Center for Homeland Security, February 1st, 2013. Cover image: Wikimedia Commons