The Grey Wolves: German U-boat Doctrine, Tonnage Warfare, and the Battle of the Atlantic, 1939–1945
The Battle of the Atlantic centered on Dönitz’s U-boat–led tonnage warfare, aiming to sink Allied shipping faster than it could be replaced. Wolfpack tactics, Type VII submarines, and Enigma initially succeeded, but Allied advances in cryptography, radar, and air power decisively broke the U-boat threat by 1943
