When I get my CHP and start carrying on a regular basis I've already instilled it in my mind that my gun is for the protection of myself first (and those immediately in my presence) and only if I can't get out. I'm not going to go out 'searching' for the shooter. Its not my job. My job is to survive, and in my mind the best way to do that if escape is impossible is to get myself into a corner against a wall (or anywhere else someone can't come up behind me) with my gun ready. If it means it saves the other people around me, then so the better. But I'm not responsible for anyone's safety other than my own, just as they aren't responsible for me.