Killing the messenger: targeting Islamic State's operatives who plot foreign attacks online

The months-long manhunt for French-born Rachid Kassim ended one chilly morning early this year when a drone-launched missile destroyed his battered white pickup truck as it motored through the besieged Iraqi city of Mosul. The 29-year-old former rapper had cast a grim shadow in international counter-terrorism circles. He spoke fluent French, once beheaded a man in an online video and allegedly helped organize or encourage nine terrorist plots -- nearly all unsuccessful -- in France last year. The Feb. 8 drone strike notched a victory for a U.S.-led effort that seeks to silence Islamic State operatives who use social media, encrypted messaging and other online tools to reach disaffected Muslims overseas and to launch what counter-terrorism experts now call "remote-controlled" attacks. As Islamic State steadily loses ground in Iraq and Syria, its ability to sponsor and inspire headline-grabbing attacks abroad looms larger than ever -- providing the militants the appearance of lethal viability despite the caliphate's collapsing borders.