Churchill had the last, prophetic word: "Hitler knows that he must break us in these islands or lose the war !"
He did not "break us in these islands" (the BoB played the prime part in that), and he lost the war.
If he had broken us, then (as Wensleydale says), he would have been in a position to devote all his manpower and material to his 1941 second "Blitzkrieg", which (he hoped) would be a repeat performance of 1940. And he might well have succeeded. Who knows ?
Danny42C.