Answers to Questions by Yair Davidiy
In which month of WW2 could one look at the facts about the Reich and derive that Germany was probably going to lose the war?
https://www.quora.com/In-which-month-of-WW2-could-one-look-at-the-facts-about-the-Reich-and-derive-that-Germany-was-probably-going-to-lose-the-war/answer/Yair-Davidiy
September 1940 was probably the crucial month. This may be demonstrated by the attitude of Spain before and after.
Before then, in June 1940, following the Fall of France, the Spanish Ambassador in Germany presented a declaration by Franco that he was "ready under certain conditions to enter the war on the side of Germany and Italy".
Hitler expected a quick victory and prevaricated. In September there was the Battle of Britain in which the RAF defeated the Luftwaffe. Franco knew then that Germany was beaten. In October Hitler and Franco met ostensibly to work out an agreement for the entry of Spain on the side of the Axis. As a condition for participation Franco made demands that were consciously too high for Hitler to meet.
By September 1940 Germany had conquered all of Continental Western Europe. Its airforce however had been beaten. The USA supplied Britain with fifty old destroyers in return for bases on British possessions.
This agreement superficially was to the advantage of the USA but it was also tantamount to a guarantee of British victory. It meant a de facto commitment by America.
Nevertheless, Germany still had a lot of advantages. Its U-boat submarines were causing havoc to British supply lines. It was winning elsewhere and would go on to score victories before the tide turned. Even so, in September 1940, the psychological edge had been lost. And Franco sensed it.
The Germans also must have realized that something had changed. The attack on Russia took place in June, 1941. It had been planned to take place earlier. It may be seen as an attempt to counter-balance the British-American entente, to create a hinterland for Germany. From that point of view it was the only chance Germany had. The fate of Germany was henceforth sealed. A few British planes in the Battle of Britain, against overwhelming odds, in September, 1940, had saved civilization!