As the Pearl Harbor attack began, a U.S. cargo ship a thousand miles away in the middle of the vast Pacific Ocean mysteriously vanished along with her crew. What happened, and why? On December 7, 1941, even as Japanese carrier-launched aircraft flew toward Pearl Harbor, a small American cargo ship chartered by the Army reported that it was under attack by a submarine halfway between Seattle and Honolulu. After that one cryptic message, the humble...