The sheer amount of guns in circulation is the only thing saving America right now. The Second Amendment doesn't even matter anymore. They could outlaw guns tomorrow, and it wouldn't matter. They couldn't forcefully confiscate the guns, even if they were registered and knew exactly where to look for them.

Try finding a police force willing to drive down a dirt road in West Virginia to knock on Otis's meth shack's door, knowing he has three firearms you are supposed to confiscate from him. You can't do it.

Don't forget, automatic weapons were already in development when there were muskets, lest we forget.