If you need another thing to think about, consider this. Guns have been legal, and common in this country since its founding - for over 200 years. A hundred years ago you would have been hard pressed to find a house without a gun in it.

The mass killings are a recent phenomena. You'll have to find something else to blame it on. The Psychiatric profession that keeps administering mind altering drugs instead of boots in the ass is a good place to start.