You're making a common liberal mistake though. In Australia, they rounded up their guns in a gun confiscation and called it a "buyback" program. There was no buyback about it. It was a confiscation and if you didn't agree, you were jailed.
Can you imagine the police going door-to-door in the U.S. and rounding up privately owned weapons? You'd have civil war. Australia and the U.S. are different. Our origins aren't the same. Our founding isn't the same. You can't compare the two countries.
Call it what you want, it worked. And yes you're right trying to take Americans guns wouldn't go well but again, you can argue the methods but the result is what is being talked about and that regulation worked because it was universal and enforced by threat of real punishment. If you're going to enact gun policy, do the same, not district by district with each corner doing what they wish or you get abject failure. You can't enact the same methods but that is the most extreme example of regulation there are measures between confiscation and where we sit today.