I've never killed anyone and I hope never to have to. But I do believe that there's a emotional and mental difference between killing someone with your hands or a knife than with a gun.
If you kill someone with a knife, you're most likely going to have blood on you. There's an emotional reaction to touching blood - why else would people get squeamish at a minor cut? This serves as a deterrent. Not a perfect one of course.
If you kill someone with your hands - choke them, etc, there's much less likely to be blood but there's still very potent physical sensations. Again, emotional reaction. Again, this will serve as a deterrent.
Guns are different. You can shoot and kill from a distance, sometimes a very large distance. The potential for the emotional response is quite a bit less, and it's possible to have no response. Thus, much lower or no deterrent.
Now, consider accidents.
Knife - absolutely can kill you in an accident, but unless you're running and trip, there's a much higher chance of a knife accident resulting in a minor injury. Even in a stab accident, there's a pretty decent chance that it's not going to kill you.
Hands - depending on skill level, it's pretty hard to kill with hands. If you punch someone, they're getting bruised. Much less likely to die.
Guns - yeah, can injure, but it really depends on where you get shot. It's much easier to accidentally kill with a gun.
Incidentally, if you look historically, you can start to see changes in war once guns were introduced.
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Ideally, here's what I want:
1. universal background checks every time you buy a gun.
2. registry of guns and who owns them. Federal level would be best, but state is better than none.
3. Automatic cross reference between the registries and individuals involved in violent crimes, domestic violence incidents, have a mental illness/emotional instability that makes them prone to violence. Basically, identify people who have been or reasonably could be a threat to others and figure out who's got guns.
4. no magazines (or whatever holds the bullets) which can hold more than 10 bullets.
5. no guns that allow you to fire multiple bullets without depressing the trigger each time. That might be automatic?
6. If you fall into one or more of the categories in #3, then you can't buy guns and have to give up any guns you own (with fair market value compensation)
7. requirement that to have a gun, you also have to have gun safe and the gun must be properly secured in it.
8. buy back programs for unwanted/damaged/confiscated guns, then they're destroyed.
9. minimum age to buy a gun and a minimum age to own a gun. say 21.
I think that this would go a long way to preventing accidents and overall reducing the number of "problem" guns (ie, the ones involved in shootings, etc) while still allowing responsible people to own guns. I also don't think it's unreasonable. Sure, you have some hoops to jump through, but you're trying to acquire an object capable of killing people. It's not unreasonable to ask that you demonstrate you're not likely to use it for that purpose.