I'm not sure how we've deluded ourselves into thinking that the two are not directly related. As other commenters have mentioned, it isn't big scary guns, but the hundreds of millions of handguns everywhere and easily available in the USA that do most of the damage.
See where I just commented on the fact that our murder rate has halved since the 1970-90s period while gun ownership rates have not changed, strongly suggesting we should look elsewhere, perhaps, as I note, demographics: https://news.ycombinator.com/item?id=9838517
