> Possibly Ghandi and India's independence? I would expect if British were still a major global force after WWII and were willing to project it, there would have to be a (successful) regular war for independence.

First, that's speculation about an imagined history, not evidence. Regardless, protest can be an influence without, by itself, being decisive. Protestors don't have absolute power (a horrible idea, even to most protestors!). No single factor is decisive by itself.