In the pre-dawn darkness of December 7, 1941, five Imperial Japanese Navy submarines surfaced off the coast of Oahu. Secured to the decks of these vessels were secret weapons to be deployed for the first time in modern warfare: two-man midget submarines, intended to enter Pearl Harbor without being detected and torpedo the US Navy battleships lying at anchor there. None of them would return from their mission.“One of the last remaining and persistent mysteries of the Pearl Harbor a...