I think the reason why it's so easy to get an illegal gun is because the legal gun market is so large, which supports manufacturers existing in the first place.

I think the reason why it's so easy to get an illegal gun is because the legal gun market is so large, which supports manufacturers existing in the first place. If tomorrow guns were banned, and we melted down every existing handgun in the US, there wouldn't be anyone left making guns and selling them to civilians on an industrial scale.