history · 22 April 1942 · 82 years ago
Joseph Rochefort's cryptanalytic team based in Pearl Harbor, US Territory of Hawaii detected a concentration of Japanese warships at Rabaul, New Britain, including five carriers; while they correctly determined that Shokaku, Zuikaku, and Shoho being at Rabaul, they had mistakenly placed two others (including Kaga) at this location.
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