I for one am hesitant to support gun bans (especially targeted ones for a particular type of weapon like the AR-15 platform) because I'm concerned it might just redirect would-be mass killers into other weapons which might be worse than doing nothing at all. We've seen mass killers use guns, trucks, bombs, airplanes, anthrax via mail, poison gas, and any number of weapons and we can't ban every single thing which could kill masses of people. Sure it would be helpful if we could snap our fingers and mass shootings with assault rifles disappeared from America, but if the unintended consequence is that mass killers use different tactics the next mass killing might be a few hundred or thousand people rather than a dozen or so. Even if that didn't happen it doesn't help much if shooters just changed from AR-15s to pistols firing rifle cartridges which would be just as dangerous as assault rifles and far more concealable. Or Remington 700 "hunting rifles." Or whatever else. I think it's extremely wishful thinking to believe that banning guns would stop mass killings, hell it might not even slow it down. My hesitation isn't "no, not ever" but considering the last assault weapon ban didn't do much I'm a bit skeptical the next will help much either.