Very different indeed. We would not have cooperated and Britain would be a German-speaking northern territory of Grossdeutschland.
Oh dear, same old rubbish.
The turning point vis-a-vis Britain becoming part of the German-speaking northern territory of Grossdeutschland was the Battle of Britain in 1940.
What we really needed then were arses on seats, the seats in question being in the cockpits of Hurricanes, Spitfires, Defiants and Beaufighters. We were out-producing Germany in terms of fighter and bomber production in 1940, thanks to our own efforts, but we were short of pilots due to the attrition rate of constant warfare. Our saviours were.. the Poles.
For which 'Dziêkuj¹' to the Polish nation.