CHAPTER 1 3 WAR IN THE FAR EAS T HE High Command of the Japanese Navy did not lightly enter upo n T the Pacific war, nor were they unduly confident of the outcome . It was subsequently learned that they knew they were entering a battle fo r sea communications ; and appreciated the extent of the sea powe r wielded by their prospective adversaries. They considered, however, that the great distances of the Pacific Ocean would be a factor in their favour , and pinned their hopes of success on the assumption that they could at the outset secure command of the Western Pacific and, with interior lines of communication and the establishment of boundary defences, isolate and hold it so as to ensure, at the least, a negotiated peace favourable to Japan . In effect, the Japanese aspired to do with an ocean area what the Germans aspired to do with a continental land mass ; to make of it a secure, self- contained fortress within geographical limits of their own determination and then, if unable to achieve outright victory by the complete military defeat of their enemies, to so sap their strength and endurance as to force them to come to terms . This, however, was to start from a false premise ; for in a world war it is impossible for any but the dominant sea power to "take as much and as little of the war as he will" ;1 and Japan, who was not in that posi- tion, sought to limit her activities to a very small proportion of tha t three-fifths of the earth's surface which the seas occupy. The deciding voice in the shaping of Japan's naval strategy wa s Admiral Isoroku Yamamoto, Commander-in-Chief of the Combined Fleet . Born in 1883, Yamamoto was a graduate of the Naval Academy and Naval Staff College . A midshipman at the time of the Russo-Japanese war, he reached flag rank in 1929 . A specialist in naval aviation, he wa s Chief of the Technical Division, Department of Naval Aeronautics, i n 1930, and became Commanding Admiral, 1st Air Squadron, in 1933 . During the next six years he was, as Vice-Admiral, Chief of the Depart- ment of Naval Aeronautics and, from 1936 to 1939 was also Vice-Ministe r of the Navy. Appointed Commander-in-Chief, Combined Fleet, in August 1939, he was promoted admiral the following year. His preoccupation with naval aviation was to have far-reaching results. In the successful British attack on the Italian fleet at Taranto he had tangible evidence of its potency and ability to alter the balance of naval power at a singl e stroke. Described as a radical nationalist, he was very active politically, and was regarded in 1939 as a candidate for the Premiership. He is said to have been shrewd but of a generous nature, and pro-British in outlook . There is no doubt that Yamamoto was fully seized with the dangers his ' Francis Bacon, Essays—Of Expense : " Thus much is certain : that be that commands the sea is at great liberty, and may take as much and as little of the war as he will ." 1940-41 JAPANESE PLANS 465 country faced in resorting to war; and from the outset he was oppose d to it as being suicidal for Japan . He resisted Japan's entry into the Tri- partite Pact in September 1940, by which she formally joined in a treat y of alliance with Germany and Italy. Soon after the pact was concluded he told the Premier, Prince Konoye, that he hoped he would try to avoi d war, and that if Japan went to war her navy would "carry through for on e year, some way ; but after that I don't know" . 2 He knew that once war began there could be no half measures, and is reported to have said : "I hope that the Japanese Army realises that if this war is to be won it wil l be necessary to carry the fight into the heart of the United States an d to dictate peace terms in the White House." Yamamoto held that in the event of war Japan's only hope lay in an early victory, and that the destruction of the United States Pacific Flee t was a prerequisite thereto . Accordingly, with the threat of war increasin g after the conclusion of the Tripartite Pact, he, in January 1941, ordered "his own staff and Rear-Admiral Onishi, Chief of Staff of the XI Air Fleet",3 to study his concept of a surprise carrier-borne air attack on Pearl Harbour. No one else was taken into the secret until the table top exercises at the Naval College, Tokyo, in September 1941, when Admira l Nagano, Chief of the Naval General Staff, and the members of that staf f first learned of the project. Until then the Japanese plan in the event of war was to proceed wit h the conquest of the rich southern regions . If the United States attempted to intervene, the Pacific Fleet would be harried on its passage west by all possible means, and would be met in a weakened condition, far fro m its bases, by a superior Japanese main fleet, and destroyed in waters near Japan. Nagano and several members of the General Staff wished t o adhere to this plan, and opposed the Pearl Harbour attack in that it would bring America into the war, and was in any case too risky a n operation. However they were overruled by Yamamoto and his supporters , who argued that the United States would enter the war in any case, an d that as Japan had the ships and aircraft to carry out both the Pear l Harbour and southward attacks simultaneously, it would be foolish to let the opportunity pass. Accordingly the Pearl Harbour attack became part of the Combine d Fleet Secret Operation Order No . 1 of the 1st November 1941. This order detailed the navy's part in a far-reaching plan which was, as a preliminary and without a declaration of war, to invade Thailand, destro y the Pacific Fleet at Pearl Harbour, and attack Malaya and the Philippine s by air. The Japanese forces would then proceed with the conquest of Malaya and Singapore, the Philippines, Borneo, Sumatra, and the whol e of the Netherlands East Indies. These conquests would be secured by a "ribbon defence" running from the Kurile Islands in the north, through ' According to Admiral Toyoda (Japanese Minister of Foreign Affairs, July-October 1941) in post - war interrogation . 8 S . E . Morison, History of United States Naval Operations in World War II, Vol III (1948) , p . 83 . 466 WAR IN THE FAR EAST Nov 194 1 Wake Island, the Marshall Islands, and around the southern and western edges of the Malay Barrier, to the Burmese-Indian border . The basic plan was the conquest and securing of the southern regions . The Pearl Harbour attack was complementary but subordinate to it , designed to hasten the destruction of the Pacific Fleet and thus giv e a freer hand in the southern advance . The conquest of Hawaii was never considered. Should the Pearl Harbour attack fail to destroy or seriousl y injure the Pacific Fleet, the Japanese naval plan was to prosecute opera- tions in the southern regions with minimum strength, and revert to th e original plan of harrying the Pacific Fleet in any attempt to intervene and then fight a decisive fleet action with superior force . It was appre- ciated that it would probably be necessary rapidly to concentrate decisiv e battle strength which might be dispersed supporting invasions or taking part in combined operations but there was no detailed provision for thi s in the plans. However, to provide for possible American attacks on th e southern area task forces, some twenty large Japanese submarines operat- ing in the Hawaii area were placed under the command of the task forces commander (Vice-Admiral Kondo, Commander-in-Chief, Second Fleet) , and the main battle force under the direct control of Yamamoto in its Inland Sea bases was made responsible for providing cover as necessary. To carry their plans into operation the Japanese possessed a powerful , balanced fleet, with a large and efficient air arm . Its main units were six fleet and four light fleet aircraft carriers ; eleven battleships ; eighteen 8-inch gun cruisers; twenty-one cruisers with 6-inch or smaller guns (includin g three modern vessels of the Kashii class rated as sea-going training ships) ; about 100 fleet destroyers ; and 63 submarines, of which 42 were large operational type, ranging between 1,600 and 2,400 tons, 17 were coasta l type, and four were minelayers . Of the six fleet carriers, Akagi and Kaga, 36,000 tons, were converted battle cruisers built in the 1920's, with speeds around 28 knots ; Soryu and Hiryu, of 17,500 tons and 30 knots, were completed in the late 1930's; Zuikaku and Shokaku, laid down in 1938 and completed just before Japan entered the war, were of 30,000 tons and 30 knots . The large fleet carriers normally carried about 60 aircraft, of which 27 wer e fighters and the remainder torpedo bombers or bombers . Of the four light fleet carriers, Ryujo and Hosho were of 8,500 tons, and Zuiho and Shoho of 12,000 tons. Their normal complement was 20 to 24 aircraft, about hal f of which were fighters . In addition to the aircraft carriers there were two squadrons of seaplane carriers totalling nine (possibly more) ships, o f which four were converted merchant vessels.