They'd do better to ban the street gangs.
It's not the guns that are the problem.
They've already banned criminals, but they aren't effective in combating crime.
Instead of going after criminals, they instead create laws that just interfere with law abiding citizens and continue doing a poor job of enforcing laws.
Maybe what they need to ban is worthless politicians.
Then there wouldn't BE any politicians. Which may not be so bad, really.