"But there isn't any actual requirement for background checks or waiting periods or any other hurdle to stop you buying a gun in the USA! Gun control people in America (and indeed gun advocates, a lot of the time) usually prefer to talk of some other USA where these things are required, but it doesn't exist and there seems to be no realistic prospect that it ever will."
We don't know how this will be decided. But ts one of those issue that, for the majority of the population, has no significant impact. So why not vote in favor? Even quite a few gun owners don't see a major problem with this. One major issue that gun rights advocates have is: In order to enforce such a law, the state would need to keep a registry of gun sales transactions. It's the only reasonable way to link the current posession of a firearm to a properly conducted background check at soe previous time. And now you are building a gun registry.
My primary reason for posting this is that I don't buy arguments like "there seems to be no realistic prospect that it ever will." Yeah, right. Put that in writing someplace and I'll believe it. History is full of majorities making decisions when they don't affect themselves. Never mind what happens to the minority that has to live with the decision.