As difficult as they are to relive, the horrors of Newtown, Orlando, Las Vegas, and Parkland conceal a horrifying truth: mass shootings—incidents in which four or more individuals are shot and killed (not including the shooter)—are on the rise in the United States. They are occurring more frequently and have become more deadly. Yet following each unspeakable tragedy, as cries for reform grow increasingly shrill, gun sales rise and legislatures stonewall.