Europeans face the specter of a growing terrorist threat in their midst. On the two-year anniversary of the London train bombings, Great Britain can no longer ignore its disaffected Muslim communities. The United Kingdom has faced more attacks than any other EU country or the United States. Since September 11, 2001, Islamic extremists have carried out at least four major terrorist attacks on British soil. In the US, by contrast, only one successful attack motivated by Islamic jihad was carried out in late 2001, when letters tainted with a lethal strain of the anthrax virus killed five people.