Education.
Everything important and with risk in life requires education to own or take part of.
I can't wake up tomorrow and say, " I have the freedom to be a doctor" and be one. I can't wake up tomorrow and say, "I am a driver" and be one (clearly I am, but not related to topic)....etc etc
Just like the program that allows you to hunt, you should have to pass a program that allows you to use specific weapons. If you are still ignorant enough to think that all weapons are equal and you still hold the argument that "Hammers are more dangerous than AR-15's with 100 round drum mags" then you are just bias and ignorant to facts. Different weapons hold different powers, it's time to accept that fact. But it's also time to accept the fact that not just any ordinary "joe" should have the right to own a weapon.
The argument has been, "Innocent until proven guilty" but there is no end in that brainless argument. Guns and accessories get more dangerous every day, and the 2A was written when it took 12+ seconds to reload each round. And if you aren't stupid in politics, you know the talk isn't about guns in general...It's about the guns with the capability to hold a massacre. Most guns have the capability but only bias blinds the difference in gun/accessories/mag size strength.
I think the people should decide how much education it should take to own guns with obvious different powers. The hot weapon of topic is the AR-15. Should it take a week of 2 hour courses to obtain one? Should it take a month of horror stories and education?
Nearly nothing in America is acquired without proof of education or maturity. Yet today we are proving that these things don't matter. And note, I don't think MONEY should qualify anyone more than the next....criminals have faster ways to get money than the rest of us.