ORIGINAL: mind_messing
Would the insurrection during the War of Independence have been as widespread if the Continental Congress decided to sue for peace after Brandywine?
In the novel the US surrender is precipitated by two atomic bomb attacks that cause the US Government to sue for peace. Hearing that over the radio is a pretty big incentive to co-operate. I could understand the situation you're imagining if the government had taken the opposite tack - run for the Rockies and blast calls for insurrection all over the airways, but if you hear your government on the radio telling you that it's over, people tend to accept that it's over. August '45 in Japan is proof of that.
RE Brandywine, I don't know. There was far less cohesion as a nation at that time. As Shelby Foote said of the USA pre- and post Civil War, beforehand people spoke of "the United State are" and afterward "the United States is." The CC was pretty jury-rigged, comms were slow, and local government was given a lot more credence than central. Colonial support for the revolution differed markedly by region as well.
By 1940 that was very different. The premise of the novel demands a surrender for it to work, and I don't think one would have been forthcoming. If there had been one large swaths of the USA would have ignored it. Pearl Harbor was fairly like an atom bomb compared to peace, and Hawaii wasn't even a state. I think the ferocity of the US population would have been exponentially higher had two attacks taken place in CONUS. A president who surrendered would have been immediately impeached IMO.
For that matter, if London had fallen to Hitler would Churchill have ordered the Empire to surrender? I doubt it. And the island is tiny compared to the USA, and had far fewer weapons in private hands.
Using Japan 1945 as an argument doesn't work for either the USA of the British Empire. We don't worship our president as a god. Nor was Japan a continental power with deep natural resources and an armed population. Hence bamboo pikes on the invasion beaches.