Sure, you don't NEED automatic weapons to defend yourself, but you may be a really bad shot and need that extra fire rate or just overall prefer it. The .38 revolver and the AR-15 "assualt rifle" do the same thing: kill/injure. The only difference is how it does it. If the school shooter had a revolver, he would have still killed. In fact, he'd probably kill the same amount because of the lack of adversity he had. Banning assualt rifles and "assualt rifles" will just make people shoot with different things. In fact, almost 90% of all shootings are done with handguns.