The use of lethal violence in self-defense is perhaps not as morally gray as we might think. The 6th Commandment is "Do not murder." When, then, does taking another life constitute murder?
Before we begin, take none of what follows as legal advice. Laws vary. If anyone wants to know what the law says, ask a local lawyer. Don't get your information here.
Let us suppose someone breaks into your home and you have reason to believe your life is in danger and the only way to eliminate the danger is to take his life. That's what most of us think of as self-defense.
Now let's supposed someone breaks into your house, sees you there, says "I don't want no trouble," and flees. Would it be self-defense to shoot him? I don't think it would, since the person is no longer a threat.
Now let's say someone breaks into your home, you have reason to believe your life is in danger, and wound the person. The person is laying there, incapacitated. Would a foillow-up shot to kill him be self-defense? I don't think it would, again because the person is no longer a threat.
The common thread here is whether your life is in danger and whether the person remains a threat. If it's not in danger, then I think it's murder, not self-defense.
In the same way, if someone starts a fight and then pulls a weapon and shoots the other person, I don't think that's self-defense.
Nor is it self-defense is someone has taken your stuff and is running away. They aren't a threat. Is your stuff worth someone else's life? I don't think so.
Again, none of the above is legal advice. If you want legal advice, talk to a local lawyer.
It doesn't necessarily follow that reducing the number of firearms reduces fatal violence. 19th Century laws against Bowie knives doesn't seem to have reduced the mayhem. At the time, the lurid press portrayed them as dueling weapons, but by the 19th Century dueling was already frowned upon. That's why Aaron Burr had to go on the lam after shooting Alexander Hamilton. Even in 1804 such was frowned upon. Similarly the famous (or infamous) Vidalia Sandbar Fight happened where Samuel Wells and Thomas Maddox thought there was a question of legal jurisdiction and they could get away with it. Yet incidents seemed to have decreased, judging by the lurid stories in the press. Given that the British had a ready market for Bowie knives in the US and that any competent blacksmith could make one, neither laws nor the availability of knives had an impact in reducing incidents. Again, if the press can be trusted, the stories they did report happened despite laws designed to curb such.
I don't think we need to go over the lack of success of 20th Century laws banning switchblades in reducing gang violence. Any difficulty in obtaining switchblades was offset by other means.
That's how such things work. The problem is the intent to do harm, and that exists regardless of the weapon. We had ready access to firearms in an age when you could buy them through the mail without going through a firearms dealer and knowledge of how to use them, and we never considered such things touted today as an excuse to ban firearms. If availability is the problem there should have been more incidents when there was easier access to firearms than there is now.
I don't think it's a coincidence that such things increased after banning religious instruction in public school. The way things are now, that's apt to cause howls of protest even in the Christians' section, but there is it. We at least had memories of such instruction after such was banned, and I'm convinced that made a positive difference.
