If hitler had kept his alliance with the USSR and just took out great britan, He could have steamrolled them. But his eyes were set eastward, And those eyes ended up costing him the war, His reputation, And his life. Don't mess with Russia. Ever. Or else you will die.
Died on the east front. We supplied them and they fought. They played a important role but keep in mind we did not trust them and they did not trust us. Stalin kill millions of his own. In the end they were important but Stalin was equally has mentally ill and evil has Hitler.
But the enemy of my enemy is my friend.
Till the second that Enemy is removed.