Long before Isis, Al-Queda, or any of the other terrorist organizations got around to murdering people in the US, we had domestic terrorists (think the Weather Underground, Symbionese Liberation Army, The Chicago 7, the Ku Klux Klan, the Mafia, etc) and border security wasn't the problem.
Gun control should consist of not only the ability to properly use a fire arm, how to handle it when not in use, and most importantly, WHEN the proper time to use it is.
This schlub hasn't mastered those three things.