[Fiji Hill]

The biggest flaw of Barbarosa was even attempting it.

While still at war with the 700-million-strong British Empire, Hitler took on the Soviet Union, which is essentially a continent. A few months later, he declared war on the US, another continent-sized nation. What folk singer Carson Robison said of the Japanese can be applied to the Nazis as well:

So now, they want to fight.
Well, they've bit off quite a bite,
And Uncle Sam is going to make them chew it.

[C. Edmund Wright]

yeah, Uncle Sam did make them chew it, but so did Uncle Joe.....