239 years ago a bunch of uppity colonials decided to quit on the British Empire. This has almost universally come to be thought of as "a bad thing".
The former colonists would Found a country that would be thought of by other countries as as consisting of a bunch of overweight, none too bright hicks with a gun fetish & a tendency to sue each other at the drop of a hat.
The Empire on the other hand would decline to the point where, well it wasn't an empire at all anymore. It's people would go on to be both inordinately proud & utterly ashamed of their country's history, spending most of their time either apologising for having once been an empire, apologising for not being an empire anymore or, oddly, apologising for still being an empire (which we aren't).
All of this could have been avoided if those damn colonists had just accepted their place in the Empire instead of labouring under the deluded belief that they could actually make a successful independent country.
I mean what did the US ever give the world? Apart from the swivel chair obviously.
Actually fuck it, swivel chairs are cool. Maybe it was worth it after all.