Use it or lose it.

You can go buy a couple of guns, legally, and start shooting random people in a classroom. Or a mall. Or from your roof. You can do that. You might have to fill out a questionnaire. Wait out a background check. Even have to wait a few days. But you can do it. There's no way to stop you. You would have to get rid of guns. We would have to just get rid of them all. But we have a right to protect ourselves. With a gun. If only more of us took advantage of that right, then shootings wouldn't happen. Or maybe the shootings just wouldn't go on as long. It's all or nothing. Take your pick.