Before committing suicide in his Berlin bunker, Adolf Hitler made a will naming as his successor one of his most ruthless military associates: Grand Admiral of the German Fleet Karl Dönitz. Known as der Löwe (the Lion), Donitz had masterminded the submarine campaign that destroyed about 15 million tons of Allied and neutral shipping, with a loss of tens of thousands of Allied lives in World War II. "Kill and keep on killing," jug-eared, ice-blue-eyed Dönitz had exhorted his U-boat captains. "Remember, no survivors. Humanity is a weakness." The U-boatmen responded by firing on torpedoed crews struggling in the water.
On the...