I think there is an alternate interpretation (or at least just a reinforcement of my own beliefs) that the nation state should just occupy that local / regional level. We consolidated nations and built empires because of the logistical and militaristic needs of organization in the 18th, 19th, and early 20th centuries. Since WW2, though, we have:
* Solved the logistical problem with the adoption of wide area communications networks, enabling instant communication and more importantly negotiations between independent regions and areas anywhere in the world.
* Solved the military problem with the development of world-wrecking nuclear weapons, whose presence equalizes all involved nations such that it does not matter if you have a giant population and production machine to build every other weapon of war - the danger of just a few dozen advanced nuclear weapons in arsenal deters any reasonable nation from attempting invasion because that many bombs could render the Earth uninhabitable.
Additionally, computers ease the burden of managing international relations between potentially thousands of participating bodies by instituting protcol standards between them and the Internet gives us an environment to broadcast transparently the terms of interaction between nations, and those can be updated in real time in ways a generation ago couldn't consider possible.
Now there is no good motivation to maintain giant nation states. Letting large countries break up into smaller, more focused soverignties handling their own affairs maximizes liberty for the people. And the international economy can be very effective as a tool of global governance - if you and most nations agree on something, and think it is important enough, you can embargo the dissenters to put economic pressure on them to reform. Likewise, for any noble cause, you can accept the burden of economic isolation to prove your point and then campaign to change the minds of citizens in other countries.
If governance were localized like this, you would not run into the apathetic superstate of the modern age where citizens demands are very often ignored. When a legislature only rules a few million people, individual voices are louder, and deposing the corrupt is much more straightforward - even if it requires violence. The larger and more expansive the sovereignty the more detached from any one locality it becomes until it is just detached from everyone operating as this global influence without oversight.
* Solved the logistical problem with the adoption of wide area communications networks, enabling instant communication and more importantly negotiations between independent regions and areas anywhere in the world.
* Solved the military problem with the development of world-wrecking nuclear weapons, whose presence equalizes all involved nations such that it does not matter if you have a giant population and production machine to build every other weapon of war - the danger of just a few dozen advanced nuclear weapons in arsenal deters any reasonable nation from attempting invasion because that many bombs could render the Earth uninhabitable.
Additionally, computers ease the burden of managing international relations between potentially thousands of participating bodies by instituting protcol standards between them and the Internet gives us an environment to broadcast transparently the terms of interaction between nations, and those can be updated in real time in ways a generation ago couldn't consider possible.
Now there is no good motivation to maintain giant nation states. Letting large countries break up into smaller, more focused soverignties handling their own affairs maximizes liberty for the people. And the international economy can be very effective as a tool of global governance - if you and most nations agree on something, and think it is important enough, you can embargo the dissenters to put economic pressure on them to reform. Likewise, for any noble cause, you can accept the burden of economic isolation to prove your point and then campaign to change the minds of citizens in other countries.
If governance were localized like this, you would not run into the apathetic superstate of the modern age where citizens demands are very often ignored. When a legislature only rules a few million people, individual voices are louder, and deposing the corrupt is much more straightforward - even if it requires violence. The larger and more expansive the sovereignty the more detached from any one locality it becomes until it is just detached from everyone operating as this global influence without oversight.