There are many parallels between Hitler and Stalin. On the personal level, they both liked to conduct all-night meetings. On a more critical level, the purge of the Red Army command that Stalin carried out before World War II in order to consolidate his hold on power left the Red Army ill equipped to handle Hitler’s invasion.

While Hitler didn’t order his army command, aside from those who tried to assassinate him, executed, he regularly demoted generals (only later to often promote them again). As a self-styled military strategist prone to overruling his command, he regularly put the Wehrmacht in compromising positions. But while Stalin was able to overcome handicapping Russia at the start of the war, Hitler was not as lucky with another of his purges. In his classic The Second World War (Penguin 1990), which I just finished reading, John Keegan, the eminent ― and eminently readable ― British military historian who died last year, explains. After mentioning the Manhattan Project, of Germany’s nascent atomic weapons program he writes:

It was the crowning mercy of the Second World War that it came to nothing. For a complex of reasons, which included Nazi Germany’s self-deprivation of significant scientific talent by its persecution of the Jews … the American atomic intelligence team which ransacked Germany in May 1945 found that ‘they were about as far as we were in 194l, before we had begun any large-scale work on the bomb at all’. … the evidence showed that, ‘although [Hitler] had been advised of the possibility of an [American] atomic weapon in 1942, the Germans had failed to separate U 235 (the essential fissile element) and that, while they had apparently started separation on a small scale by means of a centrifuge and were constructing a uranium pile, they had only recently succeeded in manufacturing uranium metal.’

… In short, the Germans were years from manufacturing an atomic bomb at the time when the Allied atomic weapons programme was already close to fulfilment.

Just as Hitler was unable to overcome his inflated opinion of his military expertise, he was unable to overcome his hatred of Jews, who, if allowed to participate in his nuclear-weapons development program, might have succeeded. Meanwhile, in 1939, Albert Einstein, who emigrated from Germany early in Hitler’s rule, wrote to President Roosevelt to warn him about the German program and suggest considering embarking on one of his own.

Arguably the use of nuclear weapons by the United States wasn’t the deciding factor in winning the Pacific or even in keeping the peace during the Cold War. Nor was Einstein, otherwise a pacifist, without regrets about the impetus he gave to the U.S. nuclear-weapons program

Joseph Goebbels famously said, “Jewish intellectualism is dead.” In the process, though, not only was German life of the mind, but know-how, dealt a critical blow. By excising what it thought was a tumor ― Jews ― Germany was actually giving itself a partial lobotomy.