British empire did war mostly on the sea, so US and British Empire were much better at producing ships, aircrafts, and also radio, radars and other electronics.

Tanks is good but it is much less important than strategy, logistics, food, drugs and saving human lives.

USSR killed a huge number of own citizens (including execution of so called deserters). Well, good for the rest of allies.

Stalin fleeced the Kuleks to pay for Americans to build factories just before WW2, after Ford's River Rouge industrial city was completed.

He did a good job on T-34 production, but around half of Soviet armaments came from the USA during WW2. The tanks were directly driven to the front - no parking lot needed! :)

Stalin is portayed as a monster because he was. But he was also the great leader his country needed at that time.