You've already agreed that those countries are those countries and are *not* the United States.

Of course. But it means that it is more likely that such an outcome could exist in the U.S. than, say, eliminating sadness or achieving immortality. There are quite a few nations that have successfully reduced civilian ownership of firearms to a negligible number. It is a policy outcome that is achievable, in practice, in actual countries that exist. There are certainly factors that make achieving that outcome more or less likely in different countries, of course. But it's not "utopian" in the sense that other wished-for goals are.

Uhhh.... I see I need to add more air quotes: " " boating accident " ", as the joke goes, is a euphemism for All my weapons mysteriously vanished, officer. I have no clue where they went. The point being, of course, that absolutely nothing happened to any of them.

Why do you think that would be successful? Officers typically don't just take people's word that they aren't in possession of illegal items. That "boating accident" response is so implausible that law enforcement isn't going to accept it.