I've often wondered, if a country decides to ban guns, how they'd go about seizing all the millions of firearms kept by millions of people in their homes? An amnesty wouldn't be terribly effective; folk would hang on grimly to their guns at all costs, and there must be vast numbers in the USA. One could hardly raid private premises like the Gestapo and root through people's cupboards and drawers.
Here in UK we seldom see 'a gun', except in the possession of, say Airport Police. I've no doubt many are out there, but it certainly isn't the norm, thank goodness.