Problem is the proliferation of guns with no regulation.
We regulate driver cars far more stringently than gun ownership.
If I'm in an open space with an active shooter, who should I fear more - the shooter or some amateur idiots with guns who haven't been to a gun range in 2 years?
If we are going to have widespread gun ownership:
1) owners have to be vetted for basic sanity, and all gun sales registered.
2) owners have to pass gun safety class (just like driver ed), and show they can actually use a gun (like a drivers test for a license)
3) owners have to renew their license on a regular basis and are legally responsible for securing their guns (i.e. if you don't properly store a gun and it's stolen and used in a crime, you're liable and maybe criminally negligent)
4) all ammunition sales should be monitored, and built so it can be traced back to the purchaser. Like guns, purchasers of bullets should be held legally responsible for safely securing their ammunition.
5) ban assault rifles - they are only good for murdering people, in close quarters like protecting your house, a pistol or shotgun is far more effective. No, you're not going to stop an Abrams tank or Apache attack helicopter - so let's drop the fantasy of an armed citizenry stopping a military takeover. If that's what worries you, bring back the universal draft so the armed forces reflect the American people.
Production or possession of a "ghost gun" should be a mandtory five year jail term.