It can’t be denied that the cool factor is part of the popularity of the AR-15. “Tactical” is close to an erotic adjective in certain circles, and where aghast liberals see a certain brutalism in the military lines of the AR-15, others see clean lines, utility, and tactical badassery. Some folks like Ferraris, others prefer Volkswagens. To what extent the aesthetic is integral to the rifle’s popularity is unclear, and whether that aesthetic appeals to psychopaths more than to law-abiding citizens is unclearer by orders of magnitude. Some on the left have made a to-do over the fact that the Aurora, Newtown, and Portland shooters used AR-15 variants. But the rifle’s very popularity renders this coincidence statistically unsurprising — and inert. If the last three mass shooters used the same obscure receiver chambered for the same obscure round, it might be interesting. That they used a platform coveted by half of the gun-owning country tells you little. Besides, if the gun used in Newtown was indeed legal under Connecticut’s “assault weapons” restrictions — which mirror the expired federal ban — it would have lacked, at least, the muzzle device and collapsible stock of models like the OBA 7.62. These bells and whistles may add to the sexiness of the AR-15 family, but they also convince the Williamses and Lettermans of the urban east that they’re fit only for hunting Martians, rather than varmints.