Great concept, but I can see the argument that you just want to see poor anti gun liberal children being scared and murderized by a mean terrible scary assault gun thingy.
A better idea might be to meme "Rage Against The Gun (Not the Shooter)"
Or something to point out they have ZERO HATE towards the "shooter" (ahem, if he actually even shot anything), but they are all SUPER ENRAGED toward the inanimate GUN.