I understand that this is one of the arguments people make in advocating for CC, but that's a pretty limited reason for supporting it. I volunteer as armed security for our church, and we're going for active shooter training next month, so while working in that capacity I have an obligation to confront an attacker. That being said, when I obtained my CC permit my main consideration was the protection of myself and my family. I was a LEO and know first hand how seldom LEO's arrive at a crime scene in time to stop the attack. In regards to a mass shooter, I'm not saying I would or wouldn't confront an attacker outside of my obligations at church. I don't know what I'd do and hope I never find out. Concealed carry permit holders have stopped attacks in the past, certainly not all of them, but to the extent they have they've saved lives. Acting as a deterent for mass shootings shouldn't be a focus of why we're allowed to carry. Edit to add: IMO the relevant question is if you find yourself in a situation where someone is trying to take your life, whether it’s a mass shooter or someone else, would you rather be armed or unarmed? Being armed is not a guarantee that you’ll survive, but it certainly increases your chances of doing so.