That is actually a great question.
There is USA, there is Canada which has never declared independence, and I can't say outright that Canada is a worse country than USA, or has less self-determination, after taking population and geography into account. USA did lose quite a large amount of men in independence-related wars, though.
The same question about the French Revolution. Yes, they have no choice but praise it now, but Britain had no revolution and we are all now writing in English. Had France averted Revolution, it is likely that we would all be writing in French now, and English would be a niche language of England and some very backwards African ex-colonies. Was it worth it? Sure, French Revolution led to Napoleon, who could be a success had he not jump under the Russian steamroller.
The best thing about revolutions is not having them and waiting for a bigger sucker to have one. The benefits of somebody out there having a revolution seem to be shared, whereas the cost seems to be footed by the ones who did it to their country.
These suckers then have no choice but to make their largest failure the central point of their ideology. France did, so did USSR and arguably USA, however here it's not as clear-cut.