I hate to break your bubble but humans have been shitty to one another since the dawn of time and most of the time the motive is at best fuzzy. Mass shootings has basically stoped and the most of them post port Arthur are family tragedies. Before port Arthur you can see, some times multiple a year, shooting sprees but that basically stopped.

Edit: After re reading you answer I saw that i basically parroted your reply. What I'm saying is that people will always do shitty thing even a total gun ban won't change that but it will stop some of the shitty things that happens.