As early as the spring of 1944, the high commands of the Japanese Army and Navy in the Imperial General Headquarters (IGHQ)2 had, with some accuracy, predicted the trend of American strategy in Pacific War. The Japanese foresaw that the turning point of the conflict would begin developing in March or April in the Marianas. Further, the military chiefs were concerned with what Japanese strategy should be at this critical time.
The Japanese Situation1
Faced with an impending accelerated American drive in the Central Pacific, IGHQ issued an Army-Navy agreement for Japanese operations in that area. The Navy was given primary responsibility for denying the Allies bases from which further operations could be launched against other islands and finally Japan itself. By the spring of 1944, defenses in the Carolines, Marianas, and Volcano Islands were to be completed. Japanese Army units were to reinforce the island defenses and would operate under overall naval control in conducting ground operations.3 A broader aspect of Japanese strategy was the decision to try to entrap and defeat decisively a major portion of U.S. naval forces. As island defenses were being strengthened, the Japanese Navy committed the bulk of its aerial strength--about 1,000 aircraft of which only 650 were operational4--to the Marianas and part of the remainder to the Carolines. Meanwhile, surface forces were to remain alert and ready to steam into combat when the time to strike arose.
Most IGHQ officers and government officials alike were supremely confident of winning the war and directed every
effort to ensure an ultimate Japanese victory. Not so certain that Japan was going to be the victor was an opposition group composed of former ministers, cabinet members, and elder statesmen (Jushin) who had opposed the war in the pre-Pearl Harbor period. Also in this group were some other influential Japanese leaders who, while not holding positions of power, had given mere lip service to their nation's involvement in a conflict. Rounding out the opposition were other formerly powerful men, who had "retired" in the early years of the war. The original doubts of the opposition gave it a basis for believing as early as the spring of 1944 that Japan was faced with inexorable defeat. These beliefs were buttressed by a demonstration of the American determination to fight aggressively and an ability to mount successful operations in the Pacific even before a second front had been opened in Europe. Alone, these two factors gave portents of disaster to those Japanese who were able to interpret them.5
Between September 1943 and February 1944, Rear Admiral Sokichi Takagi, chief of the Naval Ministry's research section, prepared a study of Japanese lessons learned in the fighting to that date. He maintained that it was impossible to continue the war and that it was manifestly impossible for Japan to win. He thus "corroborated an estimate made by top Japanese naval officers before 1941. At that time, they concluded that unless the war was won before the end of 1943, Japan was doomed, for it did not have the resources to continue the war after that time.
Takagi's study and his conclusions were based on an analysis of fleet, air, and merchant shipping losses as of the last of 1943. He pointed out the serious difficulty Japan was facing in importing essential materials, high-level confusion regarding war aims and the direction of the war and the growing feeling among some political and military leaders that General Hideki Tojo, Prime Minister since 1941, should be removed from office.
Takagi stated also that both the possibility of American bombing raids on Japan and the inability of the Japanese to obtain essential raw and finished products dictated that the nation should seek a compromise peace immediately. In March he presented his findings orally to two influential naval officers, Admiral Mitsumasa Yonai, a former prime minister, and Vice Admiral Seibi Inouye, who employed the facts of the study to induce other members of the opposition to take firm steps to help change the course that Japan was travelling.6
Less than two months after the invasion of Normandy in June 1944, Japanese leaders began receiving reports of the massive numbers of men and amount of materiel that the Allies were able to land unopposed each day on the French coast. As a Japanese foreign ministry official later wrote:
That was more than enough to dishearten us, the defenses of our home islands were far more vulnerable than the European invasion coast. Our amazement
was boundless when we saw the American forces land on Saipan only ten days after D day in Europe. The Allies could execute simultaneous full-scale offensives in both European and Asiatic theaters!7
By all accounts, Japanese and other, what really tipped the scales in favor of an eventual Allied victory in the Pacific, and more immediately caused the fall of the Tojo government, were the landings at Saipan and Japanese losses in the First Battle of the Philippine Sea. Only 1,350 miles from Tokyo, Saipan constituted one of the most vital points in the Japanese outer defense system. Toshikasu Kase, the foreign ministry official quoted above, wrote that the island:
. . . .was so strongly defended that it was considered impregnable. More than once I was told by the officers of the General Staff that Saipan was absolutely invincible. Our Supreme Command,however, made a strategic miscalculation. Anticipating an early attack on Palau Island, they transferred there the main fleet and the land-based air forces in order to deal a smashing blow to the hostile navy. The result was that Saipan, lacking both naval and air protection, proved surprisingly vulnerable.8
An even greater disaster befell the Japanese in the Battle of the Philippine Sea, 19-20 June 1944. This two-day conflict began when carrier-based aircraft of the Japanese First Mobile Fleet attacked Admiral Spruance's Fifth Fleet while it covered the Saipan operation. On the first day, two U.S. battleships, two carriers, and a heavy cruiser were damaged; the Japanese lost over 300 aircraft and two carriers. Pilots from Vice Admiral Marc A. Mitscher's fast carrier task force struck back violently the next day, sinking another enemy carrier and downing many Japanese planes. According to American estimates, their opponents suffered staggering losses in the two days: 426 carrier planes and 31 float planes. In addition, the Americans claimed that approximately 50 Guam-based aircraft had been destroyed.9
Japanese sources confirm the loss of carriers and state that four others of the nine committed in the fight were damaged. Enemy records show that of the 360 carrier-based aircraft sent to attack the American fleet, only 25 survived. "Although no battleships or cruisers were sunk, . . . the loss of aircraft carriers proved an almost fatal blow to the Japanese navy. with the loss of the decisive aerial and naval battles, the Marianas were lost."10 Despite this thorough defeat, most Japanese were told that it was a glorious victory for them; "it was customary for GH [IGHQ] to make false announcements of victory in utter disregard of facts, and for the elated and complacent public to believe in them."11
Although the Japanese government did not announce its losses in the Battle of the Philippine Sea--or that it had even lost the battle--news of the fall of Saipan was made public. Upon learning this in July, an opposition group consisting mainly of Jushin determined to
overthrow the Tojo regime, and forced the Prime Minister to resign from office on 18 July 1944.
The problems facing Japan were hardly resolved with the appointment and installation of General Kuniaki Koiso as premier. The Japanese Army was still a political power, capable of dictating the rise, fall, and course of government, and Tojo and his followers remained uncontrite in their adherence to a chauvinistic program of Japanese conquest and supremacy. Although the Home Islands had not yet experienced the devastation and chaos to be brought by the vast Allied air raids, after the fall of Saipan a number of critical domestic problems affecting the war effort faced the Japanese government. The output of a number of essential items fell below peak requirements, and severe shipping losses reduced the amount of raw and finished material reaching Japanese shores to a point far short of needs.
On the home front, despite its unhappiness with Tojo and his handling of the war, the Japanese public was confident in ultimate victory. Those leaders in government opposed to the war, opposition leaders behind the scenes, and some of the war hawks, too, began to have greater misgivings as they learned of previous defeats and potential disasters. As this knowledge spread, the military factions slowly lost face and became discredited, but not until the last months of the war did they lose power.
Nonetheless, confident of their ability to guide Japan to what they considered would be a just victory, the military leaders made adjustment after adjustment in strategy and troop dispositions in one area after another as the Allied threat to the Home Islands intensified and accelerated. On the other hand, it is possible to understand their reluctance to view the situation realistically. From their earliest days, Japanese citizens were taught to believe that the one alternative to victory was death and that surrender was so disgraceful as to be unthinkable. And the high command planned, therefore, to continue the war, even on Japanese soil if necessary, but to fight to the finish in any case.
Even lower ranking Japanese Army and Navy officers, many of them products of a prewar conscript system, who very often came from peasant families, held the same beliefs as their seniors regarding honor and obedience and the disgrace of surrendering. The code of the samurai had been all-pervasive for many years and had influenced the attitude and outlook of nearly every facet of Japanese society.
IGHQ took steps for the defense of the homeland as early as the beginning of 1944, when it perceived the course that the war was taking and judged what future American strategy was to be. Japanese strategists believed that Allied forces would attack Japan proper from the direction of the Marianas and through the Philippines. The Tokyo headquarters prepared for this eventuality by setting up a defense line along the sea front connecting the Philippines, Formosa, the Ryukyu Islands, the Japanese homeland, and the Kurile Islands, and strengthened the garrisons on each. According to this plan, the Japanese would concentrate their full strength
to destroy the Allied threat at whatever point it developed.
A schedule of four prepared reactions, called the SHO-GO operations, was drawn up. For the defense of Formosa and the Nansei group, SHO-GO No. 2, IGHQ placed the Thirty-second Army under the command of the Formosa Army in July 1944, and added two divisions to the order of battle of the former. In the 10 months between the landing on Saipan and the invasion of Okinawa, Japanese strength was built up in the Ryukyus from an estimated 10,000 to approximately 155,000 air, ground, and naval troops.12
For the defense of the Philippines, the high command had planned SHO-GO No. 1. Based on a decision of the Imperial War Council on 19 August 1944, Japan staked her national destiny on the outcome of the impending battle of Leyte.13 It was here that the Army and Navy had to destroy the Americans. The critical losses sustained by the Combined Fleet in the four-day battle for Leyte Gulf, 23-26 October 1944, three days after the invasion of Leyte, and the inability of ground forces to contain the invaders, created a grave threat to Japanese hegemony in the Western Pacific and even more so to the safety of Japan proper, Allied task forces dominated the waters surrounding Japan proper and the East and South China Seas as well. An additional liability resulting from American successes was the concomitant loss of airdromes from which land-based planes could pummel Japan unmercifully.
Seeing that no good purpose would be served by prolonging the Leyte operation, IGHQ decided to withdraw Japanese forces from the island and to conduct delaying tactics elsewhere in the Philippines. The Luzon landing in January 1945 made it apparent that there was no further way of holding off the Americans. From November 1944 on, American air attacks on Tokyo, Nagoya, Osaka, and northern Kyushu increased in intensity, destroying great sections of these areas and seriously impeding the war effort.
In January, the overall IGHQ estimate of the situation concluded that although Japan and Germany had suffered many reverses, the Axis had exacted a heavy penalty of their enemy. In viewing the Japanese cause in the same way that the viewed the Emperor and sacred homeland---through an emotional and reverent haze14---the senior commanders concluded that "the final victory will be for those who will stand up against increasing hardship and will fight to the last with a firm belief in ultimate victory."15 While it acknowledged that the defeat of Germany would mean the unleashing of tremendously powerful forces against Japan, IGHQ believed that one of the major American problems would be in the area of manpower mobilization. The Japanese commanders hoped that, tiring of the war, the American people would favor its end.16
Believing that the United States wanted to terminate the war quickly, IGHQ speculated that American forces would take the shortest possible route leading to Japan, This estimate foresaw that after the landings in the Philippines, the Allies would move to Formosa, Okinawa, and Iwo Jima. Based on the fact that most Japanese supply lines to the south had been well interdicted early in 1945, and an interpretation of radio intelligence reports, it seemed very likely that Iwo Jima was to be attacked in the very near future.17 IGHQ also speculated that American forces would land on mainland China in southern Kwantung and Hongkong.18
In the face of the impending invasion and to strengthen homeland defenses further, IGHQ planned a large-scale mobilization of all segments of the population. In October 1944, when the government invoked general mobilization, there were 6,390,000 reservists available for call-up. Of these, 4,690,000 were ready for immediate assignment to active duty. There was a problem, however, of achieving a proper balance in the armed forces, since a shortage of trained technical personnel existed. Moreover, of the approximately 87 percent of the Japanese adult population already employed in the vital food and munitions industries, 47 percent were reservists and not available unless the war effort was to be damaged.19
Further, at this late stage in the war, all branches of science were mobilized in the faint hope that they could develop surprise attack weapons. Unfortunately for this program, students at Army schools and serving officers were not very well trained in scientific and technological subjects; because of the nature of their duties and the weapons which the Navy employed, naval officers were in a little better position. The Army, however, was and always had been the dominant military authority in Japan, and as in the past, determined how the country would fight a war. Nevertheless, as the Japanese war situation deteriorated, military leaders optimistically sought the development of miraculously effective weapons.
Nonetheless, it became abundantly clear that the low scientific level of the nation could not possibly yield elaborate weapons. . . . The Army's attitude toward technology incurred many kinds of great criticism from private sources at the time, the major points being the following:
The Army keeps matters tightly secret. The Army has a great predilection for bamboo-spear tactics, and has little understanding of technology. . . .20
Despite the many imposing obstacles looming ahead, IGHQ prepared to execute a protracted war in the Japanese islands. The command headquarters made itself the supreme authority for the operation of the war and took steps to see that the governmental structure would be revised so that the Prime Minister would have comparable authority over political matters. In addition, the entire nation was to be mobilized and all citizens capable of bearing
weapons were to be armed. Key industries as well as the communications and transportation facilities were to be reorganized and operated by the state along rigidly controlled lines.21
As Japan was already a corporate state, i.e., a nation in which the government controlled every facet of industry and all other productive areas, and since military control of the state had been a fact of life from the time that Japan embarked upon her course of conquest in the early 1930s, there was little new in this revised policy, except for one phrase, ". . . in a military manner." This was a naked declaration of military ascendancy and control over all governmental functions. Even Tojo had given lip service to civilian primacy in nonmilitary matters. But opposition elements were not yet strong enough to take over the reins of government and to begin steps to sue for a negotiated peace; the militarists were still in power, and they continued preparations for a last-ditch fight.
IGHQ remained convinced the America was wearying of the war and that, even if this were not so, Japanese ground strength of some 4,747,000 men in uniform---a million and a half of whom were based in Japan22--was enough to prevent the Americans from reaching Japanese shores. If invaders did attempt to come ashore, homeland defense forces would drive them back into the sea. At the beginning of 1945 a large proportion of Japanese troop strength overall was tied down in China and Manchuria, however, and a smaller portion was isolated in the Central and Southwest Pacific, where replacements, reinforcements, and replenishment could not be sent. Nor could these units be withdrawn to Japan or elsewhere, so complete was the Allied encirclement. For all practical purposes, the units in the Pacific were lost to Japan and out of the war for good.
In late 1944 and early 1945, American bombings, fast carrier task force raids, and especially the submarine blockade had increased in intensity and reduced the Japanese north-south maritime shipments to a mere trickle, so that the economic structure of that country was slowly forced to a halt. Undoubtedly, the single most effective agent in this action was the blockade imposed by the ships of the U.S. Pacific submarine fleet. American submarines torpedoed or destroyed by gunfire 60 percent of the 2,117 Japanese merchant vessels, totalling 7,913,858 tons, sunk by American forces during the war. In addition, U.S. underseas forces accounted for 201 of the 686 enemy warships sunk in World War 11.23
On 13 January 1945, IGHQ was startled to learn that an entire convoy of nine tankers and its escort squadron had been sunk off Qui Nhon, a town on the east coast of French Indo-China. In face of this crowning blow and to
evade American planes and submarines, the Japanese devised a new system employing small convoys guarded by dispersed escorts instead of the larger convoys and concentrated escorts sent out previously. Even this method failed when air and naval bases on Luzon became operational and American attacks from the island quickened in pace with the submarine attacks.
At the beginning of March 1945, IGHQ stopped sending convoys to the south; northbound convoys carrying essential war material continued the attempt to reach Japanese ports, however. Some 70 to 80 percent of the ships never made it. Later in the month, Tokyo ordered shipping halted altogether.24 The noose around Japan was drawing tighter and tighter.
Since February, IGHQ had received a mounting influx of reports of increasingly larger numbers of American convoys operating in the vicinity of the Marianas and Ulithi. On 12 February, Tokyo was alerted to the movement of a sizable task force heavily protected by carriers and headed towards Iwo Jima. On the 16th, IGHQ was certain that the Bonins were the American target. When the actual invasion of Iwo began three days later, there was little doubt that Okinawa would be next.25
In March, the Army and Navy concluded yet another agreement concerning joint defense operations, this one establishing responsibilities for containing Allied advances into the East China Sea. According to the plan, when American task forces approached this area, Army and Navy air elements would mount massive attacks against the convoys. Included in the Japanese aerial formations were to be special aircraft flown by pilots trained in suicide tactics.
At the end of the month, Japanese air strength available for the defense of Okinawa was as follows:
8th Air Division (Army), Formosa; 120 fighters, 60 bombers, 10 reconnaissance planes, 250 special attack planes. The targets of the latter were American transports.
Sixth Air Army (Army), Japan; 90 fighters, 90 bombers, 45 reconnaissance aircraft, and 300 special attack planes were assigned to attack American transports; 60 fighters, 30 bombers, 20 reconnaissance aircraft, and 100 special attack planes were assigned to strike task force carriers, and Ryukuyan airfields when captured by the Americans. An additional 400 fighters and 45 reconnaissance planes were assigned to fly combat air patrols.
First Air Fleet (Navy), Formosa; 40 fighters, 40 bombers, 5 reconnaissance planes.
Third Air Fleet (Navy), Japan; 40 fighters, 30 bombers, and 20 reconnaissance planes.
Fifth Air Fleet (Navy), Japan; 200 fighters, 310 bombers, and 10 reconnaissance aircraft.
Tenth Air Fleet (Navy), Japan; 700 combat planes, 1,300 training planes. This fleet was a reserve force, and its aircraft were to be employed as special attack planes. According to the Army-Navy agreement, the Navy planes were to attack the U.S. task forces and the escort shipping guarding them. To enlarge
the number of special attack units, both the Army and the Navy were to indoctrinate their pilots "in the spirit of suicide attacks."26
From early January until the middle of March, American carrier-based pilots had battered Formosa and Okinawa in an aerial onslaught that showed no signs of letting up. It seemed inevitable to the Imperial General Headquarters that the U.S. move following Iwo would be against the Ryukyus. Late in March, the Tokyo command received word that American forces had steamed out of anchorages at Ulithi and in the Marianas. During the same period, fast carrier task force aircraft pummelled Okinawa with from 500 to 700 sorties daily. The prologue to the grand climax was reached on 26 March when the Kerama Retto was invaded; Okinawa¹s time was not far off.
Despite the clear indication that Okinawa was the major U.S. target, Japanese air strength had dwindled to the point where it was in no condition to contest the landing. The Fifth Air Fleet, with a major assignment in the defense of the Ryukyus, had been soundly crushed in February when American fast carriers visited Kyushu. The other major air commands slated for important roles in protecting Okinawa either were not yet deployed in positions from which they could fly out to hold back the impending invasion or, having been severely punished in earlier American attacks, were unable to strike back.
Japanese naval strength was hardly in better condition. The fleet was in woefully sad shape and unbalanced. The high toll in the loss of its carriers, destroyers, and aircraft had left it in a pitiable condition, while the overall shortage of fuel would have immobilized it in any case. By March 1945, it "was nothing but a partially paralyzed surviving unit."27
Following the news of the fall of Iwo Jima, the Thirty-second Army on Okinawa stood wary--listening, waiting, and watching for an invasion force to appear over the horizon. Its expectations were soon to be fulfilled.
Table of Contents ** Previous Chapter (1) * Next Chapter (3)
1. Unless otherwise indicated, the material in this chapter is derived from: Foreign Histories Div, G-3, Hq, U.S. Army Japan, Japanese Monograph No. 45, rev. ed. 1959, History of Imperial General Headquarters, Army Section (OCMH), hereafter IGHQ Hist; Robert J.C. Butow, Japan's Decision to Surrender (Stanford: Stanford University Press, 1954), hereafter Butow, Japan's Decision; Takushiro Hattori, Dai Toa Senso Zenshi [The Complete History of The Greater East Asia War], MS trans, 4 Vols (Tokyo: Matsu Publishing Co., 1955), v. IV (OCMH, DA), hereafter War History; Saburo Hayashi and Alvin Coox, Kogun (Quantico: Marine Corps Association, 1959), hereafter Hayashi and Coox, Kogun; Toshikasu Kase, Journey to the Missouri, David N. Rowe, ed. (New Haven: Yale University Press, 1950), hereafter Kase, Journey to the Missouri; USSBS, Japan's Struggle to End the War (Washington: July 1946), hereafter USSBS, Japan's Struggle.
2. IGHQ was only a term used to denote the co-equal status and existence of the Tokyo-based headquarters of the Army General Staff and the Navy General Staff and their subordinate general and special staff sections. This duality of command typified the Japanese military system not only at the highest level, but in the lower echelons also.
3. IGHQ Hist, p. 154.
4. Hayashi and Coox, Kogun, p. 106.
5. USSBS, Japan's Struggle, p. 2.
6. Ibid., p. 3.
7. Kase, Journey to the Missouri, p. 90.
8. Ibid., p. 73.
9. Samuel Eliot Morison, New Guinea and the Marianas--History of United States Naval Operations in World War II, v. VIII (Boston: Little, Brown and Company, 1960), pp. 319-321.
10. IGHQ Hist, p. 172.
11. Kase, Journey to the Missouri, p. 74.
12. MID, WD, Disposition and Movement of Japanese Ground Forces, 1941-1945, dtd 10Dec45 (OAB, NHD).
13. Hattori, War History, p. 1.
14. USSBS, Japan's Struggle, p. 2.
15. IGHQ Hist, p. 236.
17. Ibid., p. 239.
18. Chief, War History Office, Defense Agency of Japan, ltr to Hd, HistBr, G-3 Div, HQMC, dtd 4Feb66, hereafter War History Office Comments.
20. Hayashi and Coox, Kogun, pp. 118-119.
21. Hattori, War History, p. 5.
22. OCMH, DA Estimate of Japanese Strength and Disposition of Forces, dtd 0ct55, File No. 320.2, Geographic V-Japan (OCMH). This collation was derived from authoritative American intelligence sources published in 1945.
23. JANAC, Japanese Naval and Merchant Ship Losses (Feb47), pp. vi, vii, cited in Samuel Eliot Morrison, Leyte, June 1944-January 1945--History of United States Naval Operations in World War II, v. XII (Boston: Little, Brown and Company, 1958), p, 413.
24. Hattori, War History, p. 6.
25. IGHQ Hist, p. 256.
26. IGHQ Hist, pp. 274-275, 277278.
27. Hattori, War History, p. 26.