The number of magazines he had on his person is irrelevant. Hell, I'm a CCW and routinely carry extra ammo, and I would probably carry more myself at one of these rallies considering what happened in Dallas. The question is whether there was an imminent deadly threat. Based on the video, I personally don't see it. He was not surrounded, there was ample distance between he and the protesters, and the protestors aren't running toward him or doing any more than shouting at him. As far as I am concerned, it was an irresponsible use of a handgun.