I don't think it's at all true that the current United States is more loosely organized than nation-states like Poland and Lebanon, and if you want to lump nation-states together with their diametrical opposites like Belgium I have no idea what distinction between categories of polities you are trying to discuss. "Random unaffiliated, unassociated people wandering around hunting for food" is not a fair description of any state of human existence that has ever been documented by anthropologists or, to my knowledge, suggested by archaeologists. Certainly it isn't a fair description of the Holy Roman Empire.

Moreover, the particular way in which the United States discovered how to generate electricity from nuclear fission and traveled to the moon with rockets crucially depended on it not being a nation-state: it was consequently able to assimilate foreign immigrants like Fermi, von Braun, von Neumann, and Einstein.

Certainly it's possible for a nation-state to make such advances in theory, but in practice they seem to depend on the kind of diversity of intellectual and cultural traditions that is anathema to nation-states. Neither the Soviet Union nor the United States nor the countries of the European Space Agency were or are nation-states.