In June 1943, a Kentucky congressman walked up to a microphone and gave Japan one of its greatest intelligence victories of WWII.

World War II proved that control of the oceans could determine the outcome of a global conflict. While battleships had long dominated naval thinking, the war quickly showed that aircraft carriers and submarines were changing the rules.

This video features rare World War II footage of a Japanese submarine crew operating at sea. Submarines played a significant role in Pacific naval strategy, carrying out reconnaissance missions, commerce disruption,