You’re far less concerned about being stalked when you have protection.
Personally, I’m far more willing to intervene or suggest someone to stop something when I am carrying a weapon. You can protect yourself so you’re willing to say “hey man, let’s not scream on the bus”
Obviously I would (not with a weapon) step up in certain situations, but someone yelling shit on the bus? Definitely not going to engage that person, it's best to ignore and let it go.
You might enjoy this book:
https://www.amazon.com/When-Violence-Answer-Learning-Takes/d...
"Violence is rarely the answer, but when it is, it's the only answer". Kinda ups your bar about what you will let slide vs address.
Finally, shooting/stabbing/etc someone even if 100% justified has a way of wrecking your life. Your employer or coworkers find out about it? Have fun at work. Your family finds out about it? Have fun at family gatherings. Etc etc.
I’m sure everyone reading my comment in their head is imagining something different. I was imagining some one being assaulted, and wouldn’t have drawn a weapon - just spoke up.
Frankly, I don’t think pulling a gun in a crowded place would almost ever be a good idea. Unless there was already an active shooter and even then, retreat if possible.
the other obvious problem would be, presumably, that if it's genuine 'crazyness' that you're concerned with, as opposed to anti-social behaviour or drugs that tend to accompany the lack of social capital and safety nets in the US, then a gun wouldn't actually be a disincentive.
on the other hand, I'm surprised how people don't vote road rage or idiots behind the wheel as arguments against car driving.
For a tragically relevant example of genuine crazy behind the wheel: see https://en.m.wikipedia.org/wiki/January_2017_Melbourne_car_a...
obviously then you've also got the downside of living in the area with guns.
see gun death, murder, and car death/injury stats in US vs elsewhere, for example.
disclaimer: I live in the green areas mentioned in article, don't own a car.