This is quite true . . . France would have been "spamming" alot more invasions of England if the British Navy were all over in India and America all the time.
And if you look at it, various European factions did attempt or plan multiple invasions of Britain, both during the time period of the game and immediately before and after. That none were successful (or landed troops in England itself) had alot to do with the Royal Navy.
The Brits, on the other hand, tended to "spam" invasions all over the coasts of Europe. It was just sort of their thing.
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