Require all gun owners and everyone purchasing a firearm to undergo a psychological evaluation prior to purchasing a gun

In the wake of the recent shootings in Santa Barbara, CA, as well as the Sandy Hook Massacre, the theater shootings in Colorado, Virginia Tech, and Columbine, it appears that even mentally insane individuals can still legally purchase and acquire firearms. I propose that all gun owners as well as those seeking to purchase a firearm to undergo mandatory psychological evaluation prior to purchasing or keeping firearms. Furthermore, I propose that licensing is required to keep firearms and a psychological and physical examination is part of the requirements to renew gun ownership licenses every two years. We need to control gun violence in the United States, on the federal level, in the state level, in the county level, and in the city level. NOT ONE MORE!