"It was used to slaughter first graders at Sandy Hook, murder Batman fans at Colorado movie theater, kill county workers at a holiday party in San Bernardino. Now a descendant of the AR-15 semi-automatic rifle — a Sig Sauer MCX — has the dubious distinction of being the weapon of choice for a homosexual-hating gunman named Omar Mateen who is being blamed for the worst single-day mass shooting in U.S. history."