the merciful Hitler's Luftwaffe bombed and sunk a large portion of the Allied ships evacuating Dunkirk. Oh, and about Stalingrad - this military genius re-directed his forces southward to the Caususus with intentions of invading India. He was either a nutter, or he wanted to lose the war. For a more revealing possible explanation, look up the account of Rommel's meeting with Hitler around that time (it's supernatural).