I should probably clarify that my comments are from the perspective of an old cop and gun-toter from way back. I expect things of myself that I do not require of anyone else.
I stated earlier that I have no truck with any private citizen who avoids a confrontation with a rampaging active shooter. And yes, if you're running around waving a gun when de po-po show up, it could end badly for you. You need to think about that, and whether you and your gun are up to the fight, before covering distance toward the threat, instead of away from it.
“Nine-tenths of tactics are certain, and taught in books: but the irrational tenth is like the kingfisher flashing across the pool, and that is the test of generals. It can only be ensured by instinct, sharpened by thought practicing the stroke so often that at the crisis it is as natural as a reflex.” ~ T. E. Lawrence