So, couple of perspectives from the CCW class I took on the subject.
- You should never draw and use your weapon unless you are ready and willing to kill the target.
As others have said, you are taking an extremely final solution to a problem that could possibly be solved by other means. And once you consider the emotional, legal, and financial consequences, what level of threat justifies putting up with those consequences. The instructor (and all the fellow students with me that I spoke with) put it at immediate risk of acute physical harm to self or family, and strongly discouraged any efforts to intervene on behalf of anyone else, such as playing ‘hero’.
- If you apply (1) above, then yes, you should stop the threat.
Which meant shoot center of mass, which was approximated by target shooting at an 8.5x11 sheet of paper at ranges of about 15 feet. Why that size? Because if you do, you’re basically going to hit critical areas of the heart, arterial system, or lungs. Why that range? Because if you’re closer, things have already gone to hell and just getting a gun out is going to be problematic, and you’ve escalated a situation, and if you’re farther, you should be running away! (this doesn’t apply in a home invasion, but class tried to prepare you for multiple solutions).
- Do not try warning shots, or shoot to wound.
Mostly what people have said before. Just by drawing a weapon, or holding a weapon (in a home defense) you are escalating the conflict. Shooting accurately is hard unless you have a LOT of time and money to practice. I normally go shooting for fun around 4 times a year, and only about 200 rounds each time. Which at current prices is about $50-60 in public range fees and ammunition (and I use a cheaper caliber). I would have zero confidence in striking a moving limb, especially with my blood pumping. Shooting to wound belies point 1 and 2 as well.
Lastly, something no one has has posted about, which really, really want to address is that especially with warning shots and higher-risk wounding shots, is that you are very likely to miss with a number of your rounds. Those rounds are still lethal, still moving, and can absolutely hit an unrelated party which you are 100% responsible for. So please don’t fire a warning shot in the air, for when it comes down again, you are going to have legal issues for anyone and anything it hits. Don’t try for tricky shots, or the same applies.
I did find it funny (and rewarding) that our CCW instructor spent as much or more of his time trying to talk us out of using the training as he did preparing us for safely using the weapons. And honestly, in the 7 years I’ve had a CC permit, I’ve carried probably no more than a half dozen times after I left the pharmacy job which prompted me to get it. That year, 4 of the pharmacies in my city had been robbed, and I was feeling at risk.
And don’t even get me started about legal consequence of defending yourself at work.
So TL:DR - just don’t. Unless your are defending yourself and family against imminent injury, and if you are, yes shoot with the intention of stopping the threat with the greatest possible efficacy. If you abide by the rules above, your moral and legal responsibility should be largely resolved.