Very true. And it's not like you're just guessing here. The country's experience with Prohibition in the 1920's proves that you are correct.
But one of the defining hallmarks of liberal is not ever learning from your mistakes. You can't learn if your attitude is "We just didn't go far enough." Rather than admit when they're wrong liberals always double down on stupidity. If they could learn they wouldn't BE liberals.
Also look to Canada. They are gun paranoid, and the gun control legislation only served to make criminals of ordinary citizens (who refused to allow their arms to be confiscated, which is the end goal of gun control), and virtually ALL the gun crime is committed by thugs that don’t register their guns anyway.