I was just militating against this "german lessons" trope. The most important defences of Britain were the English Channel, the Navy and the will to fight. In the very last analysis, even were Britain somehow A-bombed, the government would have moved to Canada and Britain would have continued the fight. Or - historians among you will know that Churchill considered this -, petition the US to become the 53rd (?) state. Anything before defeat.
There was a synergy in our efforts. Except maybe for the spam.
I also seem to recall Churchill sent the Royal treasury to Canada for safekeeping, something like that? The gold and gems etc.? They most certainly would have fought on from Canada in that worst case scenario, and of course the Royal Navy is conveniently portable in service of this plan.