The US is a great example to consider: compare the odds of success of a violent secessionist movement in Hong Kong to those of the Confederacy winning the Civil War.
Sorry I wasn’t clear about what I was trying to say. My argument was that most violent independence movements aren’t successful, an example of which was the Civil War, which was also called the “War for Southern Independence” by the rebels. Having a revolution sounds great if you expect it to turn out like 1776, but the majority of the time it doesn’t work out that way.
Or perhaps a French example might be more relevant, with a single city at stake: https://en.m.wikipedia.org/wiki/Paris_Commune