Look at BJ Baldwin as an example. He went shooting yesterday to get some range therapy. Doesn't seem like killing the bad guy bothers him and didn't delete any gun related post or his IG.
He has many vids of him drawing from CCW at a range (mostly the desert).
When I mentioned mindset, what you mentioned wasn't the kind of mindset I was referring to. . .
Humans, for the most part, have a built in mechanism that makes us resistant to killing other humans, sometimes even when other people are trying to kill us. It was such a prevalent problem that the military has studied ways to get soldiers to overcome this and have gotten fairly good at it
I think drills and training help because it helps because it helps us react quickly before emotions can rear their head. So if you take a person like a domestic violence victim and hand them a gun it can be hard for them to get up the courage and actually kill their attacker who is someone they already have an attachment to.
It's been a while since I read On Killing. Have been meaning to go back and read it again.
Personally, I don't agree with that rationale for drills and training. If anything, I would say that my training would likely have me pause, even ever so slightly, due to various considerations from training. Something that someone who would shoot relatively indiscriminately might not. Yeah, I'm thinking more gangsta types, but similar thought process. They would definitely NOT be thinking about anything except "Imma gonna blast dat fool". Probably took that analogy to an extreme, but that's my point.
My thoughts of mindset is that one needs to consider those things prior to. I'm not saying that I know exactly how I would react, but from what I've been read and told by folks who have had to react, mindset is an important factor.