Its things like this that really make me wonder how we can progress as a society with nutjobs like this. Without sounding like a hippy, the world is filled with so much violence and hate. If these people (and they're all over) put more effort into building society instead of destroying we could really progress. It takes a special kind of asshole to do this.
I don't see the point in imagining a world without psychopaths. It'd be lovely, but no amount of societal structure will ever remove them, we can only try to reach them whenever possible and lessen their influence on others.
Anti-murder laws don't remove murder, but they do massively lessen it. I'm always perplexed by the idea that unless something is 100% effective, it somehow 'hasn't worked'.