Terror: When images become weapons

In June 2016, a French policeman was stabbed to death in a Paris suburb. His assailant gained access to the victim’s flat, where he murdered the policeman’s partner in front of their three-year-old son. While negotiating with members of the special forces, the murderer posted live footage of himself and his victims on Facebook. Acting in the name of the so-called Islamic State, the perpetrator, who would later be shot and killed, single-handedly applied one of the fundamental tenets of mode...