Sure but it was still unwise to attack the USSR without first finishing Britain. To do that, the reich could've used russia.
A timely military defeat of the United Kingdom was not likely as Germany could not accomplish this with the Luftwaffe and Kriegsmarine, and as far as the Soviet Union relates to the question of a British defeat, the act of empowering Stalin's regime and aiding Soviet expansion to the end being a surrender by the British and her Commonwealth, it's rather a case of cutting off one's nose to spite his face. England was entirely incapable of defeating Germany military without Soviet and U.S. intervention. World War II was the last great war of empires because it destroyed Britain and France's, and they essentially both lost something far greater than what was in their war aims the moment the world's "greatest empire" had to retreat to her home island and Paris was conquered.
It's not a question of finishing off Britain, but of creating a situation that would be so untenable and unforgiving for the British that the UK would pull out of the war. And more thought was put into this end than any real pragmatic plan to defeat and occupy the United Kingdom.
Late in 1940, Berlin could've agreed to Stalin's demand for Finland and the middle east (as the price for entering the war on the side of the axis).
Stalin probably had the foresight to understand that the Soviet Union would not need German consent to break into the Middle East. The Soviet Union and the UK were able to invade and conquer Iran as early as 1941, when the Russians were getting hammered. A Soviet-Western Allies alliance was inevitable as a resurgent Germany was an obstacle to A)Soviet domination of Eastern Europe and proliferation of Stalinism, and B) British domination of the continent. This is why Stalin offered an alliance to Britain and France long before Operation Barbarossa, but was rebuffed for fear of the spread of Communism in the Western democracies and desire to use Hitler as a buffer and even a potential proxy in a future conflict with the Soviets.
And the betrayal of Finland would have simply rendered it unable to act and assist the Axis in any meaningful way in a future, inevitable conflict, just as Estonia, Latvia, and Lithuania were.
The point is that folks often quibble over the timing of Operation Barbarossa, but I don't care if it was put off until 1945; it was a massive undertaking, and to try it at any point with a Soviet Union that would now be directly occupying Finland and all of Britain's Middle Easstern colonies and territories would be foolhardy at best, suicidal at worst. Resources were a persistent problem. And once the Soviets in their emboldened position (in this alternate scenario) captured the Romanian oilfields, it would be grim indeed.
That probably would've accomplished the vital interim goal of forcing britain to give up. How could Churchill or his policies have continued if Russia was added to britain's enemies and it lost the middle east--probably India too? And as I suggested earlier, soviet expansion might've actually helped the reich later overcome russia, by spreading soviet forces far and wide.
The failure to capture British India was a lost opportunity, but the Russians had been vying for Britain's crown jewel throughout the Great Game, and Kaiser Wilhelm II had made similar efforts throughout the Great War. The best bet here would have been a Japanese invasion coordinated with a joint German/Japanese backed uprising by Subhas Chandre Bose, but there are too many reasons to list why this ended up falling apart.
Germany's plans weren't actually as nearsighted as later historians have made them appear. The primary issue was a serious lack of cooperation from her Axis partners.
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