Since I wrote “The Sandy Hook Effect” in 2012, gun violence has continued to fill the evening news, most notably the massacre in Las Vegas on October 1, 2017. In response to that horrific event I penned an opinion editorial for The New York Times, solicited and edited by the estimable editor Bari Weiss, addressing the argument by pro-gun advocates that guns are a deterrent against tyranny. What follows is an expanded version of that op-ed that includes the problem of copycat mass murders, in which perpetrators seek fame through their murderous acts, and a simple solution to it.