In case you missed it: Pearl Harbor
Independent Institute article: Newly released naval records prove that from November 17 to 25 the United States Navy intercepted eighty-three messages that Yamamoto sent to his carriers. Part of the November 25 message read: “…the task force, keeping its movements strictly secret and maintaining close guard against submarines and aircraft, shall advance into Hawaiian waters, and upon the very opening of hostilities shall attack the main force of the United States fleet in Hawaii and deal it a mortal blow…”