The USSR is arguably a somewhat more direct comparison, the different economic system notwithstanding. That was a confederation of various nations encompassing a variety of interests of cultures.

The OG 13 colonies of the US formed their own central government from the outset even if they didn't choose to follow the French model of collectivism. It wasn't a deal where they ever existed independently of the British Empire for a long time and then chose to integrate in stages over time.