It is functionally identical but completely theoretical and not achievable in practice. There's no way you can achieve that level of homogeneous control in a la

It is functionally identical but completely theoretical and not achievable in practice. There's no way you can achieve that level of homogeneous control in a large democracy with states that have heterogeneous beliefs and political values, which is what you have when a democracy is sufficiently large. If New York was isolated totally and completely self governed, you have a hope of achieving what NZ achieves. Even a country as small as Australia is evidence of this thesis. They can get it under control in one state but a cluster pops up in another and it becomes a never ending game of whack a mole. If Australia was only Sydney, covid would be a distant memory. If Australia, population of 25 million, can't eliminate it, then trying to do so in a democracy with 300 million is a pipe dream.