At American high schools, the threat of school shootings has become omnipresent. In addition to regular drills of how to act in case of assault, security forces and metal detectors are now part of everyday life in the schools. In the name of security, a whole industry is busy developing bulletproof hoodies and blackboards, arming teachers and installing ever more surveillance devices. Is this prevention? Or a self-fulfilling prophecy? While cheerleaders rehearse, basketball teams play and homecoming queens are crowned, adults in the background prepare for the emergency: What to do if a school is attacked – from inside or outside? Behaviour and meditation training to prevent violence in the first place are one thing. More money, however, is spent on armament. The so-called security industry has long entered the school market. Todd Chandler’s restrained observation takes a look at the arms and service industries and the media, at social psychologists as well as teachers. He cleverly focuses not on individual schools and incidents but rather on how a whole system responds to a threat.