“This is sort of the new normal,” FBI Director James Comey observed after the most recent Fourth of July. Comey was talking about the ten persons who were arrested in connection with a variety of plots linked to ISIS in the weeks leading up to that national holiday. But while the threat of homegrown violent extremism inspired by either ISIS or Al Qaeda is now accepted as fact, there is still surprisingly little consensus on the potentially far greater danger posed by radicalized foreign fighters trained by ISIS, returning to their native or adopted homelands in the West, ready to carry out terrorist actions—despite the attacks that occurred in Paris last November.
Indeed, long before the latest incidents, the May 2014 killing of four people at the Jewish Museum of Belgium appeared to validate fears of the potential for violence imported from abroad. The alleged perpetrator, a twenty-nine-year-old French national of Algerian origin named Mehdi Nemmouche, reportedly had spent more than a year in Syria. When he was arrested in Marseilles days after the attack, French police found in his possession an ISIS flag and a tape recording claiming responsibility for the incident. An interview with a French hostage previously held captive in Syria by ISIS subsequently revealed that Nemmouche had not only fought with the group, but also had tortured prisoners and boasted of having committed worse atrocities.