What if Hitler had not invaded the USSR, but instead invaded the UK?

England was a much smaller country than the USSR, and a British Campaign would have likely have been much shorter and cost much less than the Russian Campaign, which had cost the Germans so much. In addition, they would not have had to fight a two front war because the Allies would have been knocked out of the war. Moreover, the Mediterranean Campaign would likely have gone much better for the Germans because they could have focused most of their efforts there instead of dividing it between the Eastern Front and the Mediterranean. In addition, they would likely have been able to knock the Allies out of North Africa as well as the Middle East.