IMO, people should be given the choice whether whey want to own a fire-arm or not. In places like Texas, where home invasions are very common, the possession of a fire-arm can save many lives. However, the government should make it impossible for people with a criminal record, and those with mental issues from obtaining fire-arms.
It sound`s nice in teory, but in real life who will judge about who have mental issues or criminal record or problem with wife and her lover. Much better would be with no gun`s at all, it would be much less suffering in the world.
I agree with you about the difficulty of determining who is stable enough. That is why we have rigorous background checks for things like carry licenses. However, violence and cruelty did not start with the invention of the gun and would not go away if all the guns magically disappeared. Violence is not caused by machines it is a behavior that has been present since before we were humans.