Yeah, I've read how that when Jefferson received a copy of the draft US Constitution while he was away in Paris he was shocked by it. He thought only a few changes needed to be made to the Articles of Confederation, which was the current constitution at the time, and actually ensured more freedom.

Some interesting counterfactual history you propose there, and possibly a lot more peaceful.

It's true that European nations still retain more of their sovereignty while in the EU than do American states, and their people still think of themselves in terms of their individual nations; but of course history and different languages and cultures help in that regard. I was pleased to see that the UK was allowed to peacefully secede from Europe, despite the fact they did not allow the American colonies to peacefully secede a couple of centuries ago. Perhaps sometimes lessons are learned from history.