70th Anniversary of D-Day

[Tonus]

Oh so basically we let Russia do all the heavy work. Conservation of energy.

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Still though what the fuck was Hitler thinking attacking Russia in any case? What a delusional fuck.

You partly answered your own question; Hitler was not completely sane (and by that time, perhaps not even partially sane) when he launched the invasion of Russia. But he did have a plan, that being to seize the Caucasus (for oil) and the Crimea (for agriculture) as well as a more ambitious plan to wipe out the Russian army and grab a shitload of territory.

But it seems that he severely underestimated both the size of the army that Russia would eventually put on the field, as well as its willingness to fight once its collective back was against the wall. Hitler had expected that the dramatic early victories (which yielded millions of prisoners and quick progress into Russian territory) would cause the Russian armed forces to collapse, making the rest of the campaign much simpler to carry out. But that didn't happen, and Hitler decided to go ahead and try to grab all of his objectives and to pretend that winter wasn't happening, with the end result being that their main success in the end was taking the city of Stalingrad, and that turned into a disaster for them.

As for letting Russia do the heavy lifting, that was probably part of the plan on the Allies side. They had no reason to trust Stalin (who merrily partitioned Poland with Germany and seemed to have no interest in helping save western Europe early in the war) and may have worried that if Russia was strong enough at the end of the war, it would try to roll across Europe and replace the Nazi empire with a Soviet one. So they probably felt that it was better to let the German war machine wear itself out at Russia's expense. That, and every man and gun that went east wasn't in a position to make the re-invasion of Europe more difficult than it already would be.