Centralization has not worked in practice, aside from skinlin game. Spain is partly an exception, because it's more federated than the united states. You don't have a national narrative and you can speak spanish. But i like your metaphor. The thing i've enjoyed so far that the most of what we've talked about is, it's better to be a mouse than an elephant.
A language, a flag, a national anthem and shared history—like a heart that has to pump harder to support a heavier body, the bigger a nation gets, the harder to curate an identity. Nassim Nicholas Taleb talks about scale and governance with EconTalk host Russ Roberts. Taleb sings the virtues of smaller relative to larger and decentralized as much as possible relative to centralized. Along the way, he provides a framework for Russia's war against Ukraine and explains why the United States has thrived despite its size and scope.