Guns are legal, after passing a background check (which needs to be enhanced).
And no one ever stole a gun. Please answer the question you've been asked numerous times. If all the guns in the world were registered and if all the gun owners of the world passed mental and criminal background checks, HOW DO YOU FIGURE YOU'RE GOING TO STOP A BAD GUY FROM KILLING PEOPLE.
If you can't at least answer that question, kindly shut the hell up.