People made the same argument in Australia.  Oddly enough, there hasn't been a mass shooting there since they banned guns.  It's almost like relying on bumper sticker slogans to set policy is a bad idea.  

Zero mass shootings is an achievable goal, sadly you and your ilk would rather see children being murdered than take any action.  You can deflect and insult all you want, but at the end of the day your politics shares in the responsibility for these crimes.