Ever since the wake-up call that was Columbine, schools and law enforcement have developed multiple strategies to prevent attacks. Indeed, the horror of Newtown needs to be seen in a context that's not defined by defeat. Remarkably, more than 120 school assaults have been thwarted in the past ten years. But, while security hardware and physical barriers can play a deterrent role, it's been psychologists - working hand in hand with law enforcement officers - who have come up with the most helpful tools to prevent violent attacks. But despite the progress made, recent attacks have revealed a gaping hole in our safety net. Can the hard-won gains made by psychologists and law enforcement be extended to the families of some of the nation's most violent individuals? Is the country ready to have a national conversation about the balance between safety and civil liberties that such interventions would require?