American revolution? Is that one a flop? (I mean for now, future trajectories aside.)

It's a good example IMO. I didn't come to my mind because I see it more as a colony liberating itself rather than internal turmoil - the ruling masters were mostly on another continent, so there was no problem of what to do with them after they lost power (and in America, the royalist fled to Canada, which was not an option in other revolutions as they didn't leave large areas of land loyal to the old order).

Quite possibly the only popular revolution of the modern age that didn't end in massacres. Probably because it was, despite all the rhetoric, controlled by a group of generally conservative oligarchs who really weren't trying to shake things up that dramatically.

It did not ended with a massacre only because it started with that. Ask ghe First Nations. Lacotas for example.

That's kind of an idiotic comment. The thirteen colonies had almost no contact with the plains tribes, like the Lacota, precisely because the British government had attempted to block passage of settlers past the Appalachians after the Seven Years War.