Originally Posted by
Mycroft
Furthermore, when they were able to put up a fight, it was largely aided by US lend/lease programs.
That's a bit of a mythical exaggeration. Lend-lease was a big help in the later phases of the war, but Russia's own production always dwarfed Germany's. Already by the Battle of Moscow, the tide had turned against the Germans, who had massively underestimated the Russian morale, manpower reserves and the administrative capabilities of the Soviet government. They were absolutely shocked when well over a million men turned up as if from nowhere.
Barbarossa was never going to succeed - there was no way to destroy the Russian army and government without thinning the German front too much.