Watch National Geographic Documentaries online: Episode 2 Pearl Harbor: Legacy of Attack

The man who will always be known for finding the Titanic, Robert Ballard, contends that there's still a lot we don't know about the Japanese attack on Pearl Harbor on the morning of December 7, 1941. And by going underwater he's determined to find out some of the lesser-known aspects of the Sunday morning when America was plunged into World War II. Everyone knows about the Japanese torpedo plane attacks, but Ballard, along with American and Japanese veterans, sought out the wreckage of a Japanese midget submarine that actually became the first casualty of the battle when it was sunk by an American destroyer an hour before the Japanese airplanes made their appearance. And while thousands pay their respects at the memorial built atop the wreckage of the sunken battleship Arizona, an elite team of divers from the National Park Service fear the old battlewagon is an "ecological time bomb" because of vast amounts of fuel oil still aboard. Diving robots equipped with cameras are used to assess the condition of the wreck, and sections of the ship not seen since the morning of the attack are viewed. This is a fascinating documentary that combines commentary by historians, including author Stephen Ambrose, with spectacular underwater photography. --Robert J. McNamara

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