The attack [of Pearl Harbor] took place [December 7, 1941] on a sunny Sunday morning. A minimal contingent of soldiers was on duty at the time. Most offices on the base were closed and many servicemen were on leave for the weekend. New technology, including the new radar mounted on Opana Point, were in place, manned and functioning at the time of the attack. The incoming Japanese attack planes were detected by the radar and reported, but were mistaken for an incoming group of American planes due from the mainland that morning. While on practice maneuvers outside the harbor that morning, an American destroyer spotted a Japanese submarine attempting to sneak into the harbor. The submarine was fired upon, immediately reported — and ignored.
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Despite these and many other warnings, Pearl Harbor
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