It wasn't gun confiscation, it was a buyback program, of newly illegal semi auto and auto firearms. We've done buybacks in the US but only on a city-wide scaled and without making those weapons illegal which doesn't work as well. The Australian buyback reduced the number of gun owners in the whole country by about 50% (you could still own manually cocked firearms), reduced gun related suicides by half with no increase in other forms of suicide, and virtually eliminated mass shootings. All because Australians had had enough and said enough is enough. We haven't seen enough kids get killed yet it appears.