The November 5th Fort Hood shooting spree by a US Army Major and psychiatrist and other recent arrests of would-be US militants threw a spotlight on the reality of a two-way threat posed by violent radicals in both the US and Europe. Two months earlier, a US citizen was charged with targeting the Copenhagen headquarters of Jyllands Posten, the Danish newspaper that published the Prophet Mohammed cartoons in 2005. These events forced a rethinking of the prevailing wisdom that characterized earlier transatlantic counter-terrorism cooperation where US-EU cooperation was organized principally against an inbound threat from Europe to the United States.

Until last year, US observers worried about homegrown terrorism largely by proxy, in foreign contexts: violent radicalization in the West appeared to be a mostly European phenomenon. The US policy debate about Muslim extremism, meanwhile, focused on the ramifications for the visa waiver program and the exchange of passenger records with European governments and airlines. American commentators regularly accused Europeans of virtually fuelling radicalization by mishandling immigrant integration, and were baffled by Europeans' debates about headscarves and Leitkultur ("guiding culture") that characterized their fitful attempts to redefine their national communities.

Americans, meanwhile, retained their confidence in the integrating power of Muslim Americans' upward mobility, a national tradition of religious pluralism and the symbols of the American dream and the melting pot. The US citizenship of those arrested on terrorism charges in the early years of the war on terror, in contrast with the European experience, appeared almost accidental. While they in Europe imposed restrictions on religious expression and debated the wisdom of granting Muslims citizenship, many in the US felt if not immune, then safely ensconced. It was thought that American Muslims would prove wholesale resistant to radicalization thanks to educational and employment opportunities. Even when US law enforcement became concerned with terrorist links in Somali communities, these appeared to be imported first-generation issues that would fade with time as the dynamic host society did its work.

But recent cases show that the combination of extreme alienation from US foreign policy, whipped up with religious fervor, can trump even the relatively harmonious multicultural setting of American society. No consensus has emerged among counter-terrorism experts as to whether the string of Americans arrested in late 2009 represent a qualitative leap over the seemingly amateurish plotters foiled in the early years of the previous administration's War on Terror. The two US converts recruited to Al Qaeda and the Taliban only briefly piqued Americans' imagination in the aftermath of 9/11. But their names have since been joined in the past several months by a gallery of US citizens and longtime residents pursued by terrorism charges, many of whom resided at length in the Washington, DC and other major metropolitan areas. The recent wave of arrests has focused the national debate away from the constitutionality of US detainee policies and towards the potential for homegrown terrorism.

Jonathan Laurence is Assistant Professor of political science at Boston College and Nonresident Senior Fellow in the Foreign Policy program at The Brookings Institution. The full article was published here by Brookings.

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