At that point your choices in a scenario are "they have guns and you don't" or "we both have guns", and honestly I'd probably say that the second one is better.
Oddly enough, from what I recall of gun violence, by the numbers (i.e. people shot and shot & killed), insofar as the victim in the encounter walking away that's largely untrue. You encounter someone armed and try to pull on them, and you're fairly significantly more likely to die because of it than otherwise. Carrying actually
increases your risk of harm and death in the case of a violent encounter.
As... well, as anyone that is actually familiar with firearm usage, especially in criminal encounters, would be able to tell you, when it comes to gun on gun violence the person that wins is almost always the person that shoots first -- and someone intending to commit violence with a firearm is going to have it pulled and be significantly more likely to pull the trigger if pressed than, y'know, your average civilian (even -- especially, to a degree, because arms carrying is known to induce a false sense of security -- someone that is trained and carrying.). You may be carrying, but that doesn't mean you're even remotely as capable of drawing and pulling in a manner that's actually going to
help you. It's notably more likely to just flat get you killed.
Firearm carrying is just... it's not a matter of actual safety, largely. Psychological safety, maybe, but physically... no. Unfortunately.
... in other news, eyetwo, a 3x increase is, uh. Not "slight". Though yeah, murder rate in particular, even gun-related murder, is significantly more complicated than just which area has the most gun owners. Violence in general is multivariate as hell.
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And yeah, true, there's going to be some people you just can't dissuade from being bigoted fuckwits. Some folks are just screwed up in the head, and there's not really any degree of persuasion that can do anything about it. Ideal is to get that percentage of the population as small as possible. Getting rid of it may never happen, but if we can get it small enough to be well contained that'd be a fairly significant victory.
In other other news, if that's the same NRA critter I'm thinking of, what's amusing is that the NRA itself pretty immediately broke association with the comment in question. The backpedal involved was worth a chuckle.