[fywacro]

Um... What about Australia? Canada? Barbados?

At least a dozen former British colonies established their independence gradually and peacefully, with the willing cooperation of the UK. No fighting, animosity, or anything that could be remotely considered a "revolution".

(Now of course, not ALL former colonies separated peacefully: India, The United States, etc. But there are plenty of examples on both sides.)

And how about Iceland?

[vorg]

You're counting country numbers instead of population numbers. China, India, and the US are all high-pop places, each supported by a major river system.