It’s not the guns, it’s the deranged lunatic behind the trigger.  Take all the guns you want from responsible gun owners and you will still have terrorists hell bent on inflicting as much harm on us as they can.  The 9/11 terrorists used airplanes, the Boston bombers used homemade bombs, the Paris attackers used suicide vest, and even though the San Bernardino killers did use firearms they were purchased by someone else.  Stop with the narrow minded focus on the tool used and address the root cause if you really want to solve the problem.