On board the flagship Nagato in the anchorage at Hashirajima, the evening of December 7 found Yamamoto, as usual, playing shogi with staff officer Watanabe. These games between Yamamoto and Watanabe usually came to an end after Yamamoto had won four times in succession, but very occasionally Watanabe instead would win several games in a row. This invariably happened when a low-pressure front was approaching; possibly Yamamoto was the type that is allergic to changes in the weather. That particular evening, however, it was fine, and Yamamoto won. They finished playing rather earlier than usual, then Yamamoto and his staff officers bathed and retired temporarily to their own cabins.
Some of them slept for two or three hours, others could not sleep at all, but not long after midnight most of the staff officers were once again assembled in small groups in the operations room. The officer on duty was air "B" staff officer Sasaki Akira.
The four walls of the operations room were plastered with large maps of the entire Pacific area and charts of various zones of Southeast Asian waters. On the table were a large globe and still more charts, and on a smaller table files of operational orders and radio messages.
Yamamoto was sitting quite still, eyes shut, in a folding chair in front of the big table at the back.
News came in of the army's landing at Kota Bharu, then of the successful landing at Bataan in the Philippines. There followed a long and trying period of waiting. Time seemed to drag interminably. An uneasy silence prevailed in the operations room. No one spoke; the only sounds were the rustle of messages being flipped over in their files and the occasional scratching of a pencil.
Across the passage lay the radio room, from which a cord led to a receiver standing on the table in the operations room, so that those present could hear directly any messages that came in. Eventually, senior staff officer Kuroshima said in a quiet voice, "It should begin any moment now."
He glanced up at the clock on the bulkhead, and a stir ran through the room. At that moment, the radio operator came running in and shouted at the staff officer on duty: "Sir--the repeated to signal."
Sasaki turned to the commander in chief. "As you hear, sir," he reported. "The message was sent at 0319 hours."
Yamamoto opened his eyes wide and nodded. His mouth turned down grimly at the corners. "Did you get that message direct from the plane?" he asked the operator. The Nagato's radio room had, in fact, received the "to, to, to, to..." direct from the skies over Oahu.
"Direct reception?" said Ugaki. "Good work!" The young operator looked pleased, saluted, and rushed out of the room again.
There followed a succession of reports from the attacking units:
"Surprise attack successful."
"Enemy warships torpedoed; outstanding results."
"Hickam Field attacked; outstanding results."
At the same time, the radio in the operations room was picking up directly a great number of uncoded radio messages from the American side. From what Ugaki says in his Sensoroku, the messages tended to be broken and jerky: "SOS--attacked by Jap bombers here...." or "Oahu attacked by Jap dive-bombers from carrier...." When Yamamoto heard one of them--"Jap!--this is the real thing"--a brief grin seemed to pass over his face.
Exactly one hour after the first assault, the second attack force led by Lieutenant Commander Shimazaki Shigekazu, 170 planes in all, swept into the skies over Pearl Harbor and also achieved considerable results before withdrawing. By the time dawn broke over Hiroshima Bay, the number of messages being received in the operations room of the Nagato was dwindling steadily.
From any point of view, the raid had been an outstanding success, and the staff officers could not conceal their jubilation; Yamamoto alone, apparently, remained sunk in apparent depression.