Gonna have to hard disagree here.
Hitler invading Russia when he did and how he did was entirely down to the absolutely existential need for its resources, by far the most important being oil, which the German economy and German war machine were running out of fast, and which they had no way of getting more of thanks to the Royal Navy blockade. They were scheduled to run out in about 1942/1943 and if they ran out their hold over their occupied lands would be terminally shaken, and they would become a sitting duck for either a soviet invasion or a British/Commonwealth invasion/liberation of France which would then probably also trigger a soviet invasion.
And frankly even this desperate gamble was better planned out by Hitler than is traditionally believed, since his aim was a mad bull dash to the Caucasus to seize all the oil and other resources there, thus giving Germany all the fuel it needed for an indefinite war while terminally starving the Soviets of fuel and food. Unfortunately for him, his generals were of the opinion that all they needed to do to defeat Russia was seize Moscow, apparently forgetting the fact they would still have several thousand miles to fall back to and continue the war, and they disobeyed his orders and diverted troops from his main aim which turned germany's slim chance of victory into an absolute certainty of defeat once the attack on the Caucasus bogged down, as it could never regain its momentum and would only be pushed back from then on.
The real major fuckup Hitler made was trusting the foreign policy advise of
a literal retard* regarding the British government/population's willingness for another war, which is why he planned out his conquest of the east with the explicit notion that Britain would never intervene and most crucially never blockade Germany's ports and starve them of the resources they needed for a protracted war.
* Seriously, it really cant be overstated how jawdroppingly terrible a diplomat and a foreign policy maker Von Ribbentrop was. Of all the bigwigs of the nazi government I think there is a very good argument that he is by far the one most responsible for the downfall of the Third Reich, just by how hilariously out of touch he was with the nations he was supposed to be the expert on, how autistically obsessed he was with his own personal grudges and fantasies at the expense of his nation's and leader's interests and needs, and how astonishingly obnoxious and repulsive he was to literally every foreign leader and ambassador he was supposed to charm and bring into an alliance with Germany.
www.wsj.com
