During the first half of 1941, while General Tomoyuki Yamashita was away, enjoying – or enduring – the hospitality of the Third Reich, great changes had been occurring in Japan. As Yamashita had been visiting the Luftwaffe bases in France – and the mysterious Kitty in Vienna – Colonel Masanobu Tsuji had been at Hainan preparing for the Nanshinron contingency, and Hideki Tojo was consolidating his power in Tokyo in a way that would culminate in his being named as prime minister on October 18, 1941.
Outside the rarified air within the Imperial Palace, Tojo was already the most powerful man in Japan well before being named to succeed Prime Minister Fumimaro Konoe. Indeed, Konoe, once considered one of Japan’s most hawkish political leaders, had been falling out of touch with the march of events.
Although the emperor had yet to sign off on the idea, Japan was preparing for war against the United States and the United Kingdom, something which both Konoe and Foreign Minister Yosuke Matsuoka were willing to accept, but which they deeply dreaded.
In the summer of 1941, both the Northern Road and the Southern Road were still options, despite all of the momentum which propelled Japan southward. At a meeting with Emperor Hirohito on July 2, the Southern Road plan, a document entitled Outline of National Policies in View of Present Developments, was presented for discussion. It began with plans to pressure the Vichy French to allow full access to Indochina for Japanese troops. Konoe expressed his reservations, as did Matsuoka, who explained that he doubted Japan could accomplish this goal in Indochina diplomatically. Yoshimichi Hara, the president of the Privy Council, went so far as to point out that Germany’s invasion of the Soviet Union ten days earlier, which seemed to be massively successful, presented Japan with a golden opportunity to take the Northern Road, attacking the Soviets as they were being hammered into submission by the Wehrmacht.
Matsuoka had signed a non-aggression pact with Stalin, and Konoe still yearned for a similar deal with the Americans. In November 1940, he had sent Kichisaburo Nomura, a former IJN admiral, to Washington as the Japanese ambassador with orders to negotiate a neutrality treaty. He even spoke privately about setting up a face-to-face meeting with President Franklin Roosevelt. There were back channel contacts and rumors, but Nomura made no substantial headway with Secretary of State Cordell Hull.
The Roosevelt Administration, strongly supportive of Chiang Kai-shek and his Nationalist Chinese Government, was increasing economic sanctions on the Japanese. Against the backdrop of ongoing Japanese atrocities in China – beginning with the infamous Rape of Nanking in 1937 – American public opinion was more strongly against Japan than Germany. In the early part of 1941, Americans were divided between isolationists and interventionists, with the latter wishing to actively support Britain against Germany, and/or China against Japan. There was virtually no support for the Axis – especially after Barbarossa.
With the Export Control Act and other measures, the Americans were tightening the screws of economic sanctions against Japan. In Japan, the momentum was slipping from the hands of diplomats, into those of the military, and the winds of that momentum blew south.
Even before Vichy France was presented with an ultimatum about Indochina, Yosuke Matsuoka got cold feet. His apprehension about pulling the United States into the war was verging on panic. Tojo demanded that Konoe sack him, and this was taken up at a cabinet meeting on July 16 that Matsuoka did not attend. The vote was unanimous. Matsuoka was replaced by Admiral Teijiro Toyoda, who issued the ultimatum to Vichy, giving them a deadline of July 24 to allow Japanese troops unfettered access to all of Indochina, and the full use of naval and military facilities.
Matsuoka was wrong about diplomacy and Vichy. Much to everyone’s surprise, the French readily agreed to the demands. In Europe, Vichy had other pressing concerns, and in Indochina itself, Governor General Jean Decoux was facing a growing challenge from Communist-inspired insurgents called the Viet Minh (Vietnam Independence League), who chose 1941 to begin their insurgency campaign against French rule.
Meanwhile in Washington, DC, Roosevelt and Hull were livid, considering Japan’s “invitation” into Indochina to be an invasion – and a Vichy–German-sponsored invasion at that. Unbeknown to the Japanese, the American cryptanalysis program code-named “Magic” had begun breaking into some Japanese diplomatic – but not military – communications in 1940, and the American military leadership did have something of an idea of what was behind Japanese actions.
On July 26, Roosevelt signed Executive Order 8832, “freezing Japanese assets in the United States in the same manner in which assets of various European countries were frozen on June 14, 1941.” The countries affected by the order in June included Albania, Andorra, Austria, Czechoslovakia, Danzig, Finland, Germany, Italy, Liechtenstein, Poland, Portugal, San Marino, Spain, Sweden, Switzerland, and the Soviet Union. Earlier orders, dating back to April 8, 1940, had frozen the assets of Axis and Axis-occupied countries including Belgium, Bulgaria, Denmark, Estonia, France, Greece, Hungary, Latvia, Lithuania, Luxembourg, the Netherlands, Norway, Romania, and Yugoslavia.
As the text of Executive Order 8832 read, “this measure, in effect, brings all financial and import and export trade transactions in which Japanese interests are involved under the control of the Government, and imposes criminal penalties for violation of the Order.”
Trade between the United States and Japan, curtailed by the Export Control Act, came abruptly to a halt. The New York Times called it “the most drastic blow short of war.”
Just how drastic was already apparent to Japanese military planners. The order essentially cut off Japan’s petroleum supply, and made the Southern Road inevitable. The Dutch East Indies were then the fourth largest oil exporter after the United States, Iran, and Romania, none of which were now accessible to Japan. Controlling the oil fields of the Indies was essential both to Japan’s war machine and to its domestic economy.
In his memoirs, Masanobu Tsuji cites a study that had been recently published, concluding that
lack of liquid fuel would be fatal to Japan. In 1941 the Army and Navy had in storage roughly 1,170,000 kiloliters of aviation petrol [about 240 million gallons], and about 4,400,000 kiloliters of ordinary petrol [about 970 million gallons] … Allowing for maintenance of fifty Army Divisions and the full strength of the Air Force, it would be impossible to carry on war against the Soviet Union for more than a year as liquid fuel supplies would be exhausted within that time.
Indochina, which had seemed to have slipped so easily beneath the big Hakko ichiu roof of Japanese domination, was the key that had opened the Southern Road. For the sake of its own prosperity, Japan now desperately needed to bring the rubber plantations, mines, and oil fields of Southeast Asia under the roof of the Greater East Asia Co-Prosperity Sphere.
The Southern Road strategy, long considered in contingency planning, now began to take focus as the primary operational plan. The immediate objective was to capture Malaya and the Dutch East Indies, which contained the raw materials which were so desperately needed – and to seize Singapore, which was the keystone of British naval strategy in the Far East.
Indeed, all operations throughout Southeast Asia, especially in the Dutch East Indies, would be difficult, or even impossible, so long as the British maintained a secure base of operations at Singapore. Knowing this, the British had spent heavily in a decade-long building program aimed at transforming the 274-square-mile island into an impregnable fortress, armed and supplied so as to hold out indefinitely against any attack.
Simultaneously, the Japanese would need to neutralize the ability of the Americans to operate in the Far East, by capturing Wake Island, Guam, and the Philippines. Operations in the Pacific islands, which became so much of a focus in the actions in the coming war, and in our collective memory of the war, were considered as a buffer to protect shipping lanes between Japan and its intended conquests in Southeast Asia.
As Louis Morton writes in Chapter IV of his history of the Philippines campaign,
the area marked for conquest formed a vast triangle, whose east arm stretched from the Kuril Islands on the north, through Wake, to the Marshall Islands. The base of the triangle was formed by a line connecting the Marshall Islands, the Bismarck Archipelago, Java, and Sumatra. The western arm extended from Malaya and southern Burma through Indochina, and thence along the China coast. The acquisition of the island-studded area would give to Japan control of the resources of southeast Asia and satisfy the national objectives in going to war. Perhaps later, if all went well, the area of conquest could be extended.
To accomplish all of this, Tojo and his fellow Southern Road proponents needed to form one more vitally essential military coalition. As Japan had allied itself with Germany, Tojo had forged an alliance for the IJA that was far more important. By 1940, strategic differences within the IJA were largely a thing of the past. However, the IJA would need to formalize a level of cooperation with its sister service – and for decades, a rival service – the IJN. It was a cooperation driven by practical necessity and the nature of the terrain. On the Northern Road, in China, Manchuria, and Siberia’s doorstep, Japanese field armies fought entire campaigns hundreds of miles from the sea on land-locked battlefields. On the Southern Road, the campaign would hinge on amphibious operations at virtually every turn, and be fought on islands and on peninsulas without adequate roads. The IJA was the essential instrument of conquest, but it needed the IJN to transport it to nearly every battlefield, and provide naval gunfire as artillery support. As we shall see, this practical collaboration worked well in the early campaigns, but the institutional rivalry simmered just beneath the surface, occasionally boiling over, and was too deeply ingrained in IJA and IJN culture ever to be resolved.
Army–Navy rivalries existed within the armed forces of most countries, and still do. However, in Imperial Japan, it was an antagonism that verged on hostility. Each side jealously guarded its own turf, considering cooperation to be a show of weakness. They each maintained their own supply system, their own respective air forces, and their own intelligence apparatus.
The IJN also maintained its own land army, roughly analogous to the US Marine Corps (USMC), which is technically a component of the US Navy. In the case of the IJN, it was the Special Naval Landing Forces (Kaigun Tokubetsu Rikusentai), which were created in 1928. Though their activities ashore were greatly overshadowed by the IJA, they had nevertheless played an important role in operations against Chinese coastal cities, and during IJN actions on Chinese rivers, during the 1930s.
The Americans deliberately created a formal Joint Chiefs of Staff to streamline cooperation. This encouraged liaison at the highest levels and greatly improved relations between the Army and the Navy. By contrast, the Japanese services cooperated only when absolutely necessary, and with few exceptions, remained inherantly distrustful of one another throughout the war.
As in the IJA, the IJN was dominated by officers who believed in the projection of Japanese power throughout the Far East, but like the earlier rebel factions within the IJA, the naval officers were strongly opposed to Japanese expansion in China, and tying down forces in Manchukuo. Like the Southern Road advocates within the IJA, and the Greater East Asia Co-Prosperity Sphere advocates in the Japanese government, they understood that Japan’s future lay not in northeast Asia, but in Southeast Asia, with its great oil fields and other strategic natural resources.
Japan’s naval officers understood that the key to Southeast Asia was not only controlling the sea lanes within Southeast Asia, though this was vital, but in controlling the Pacific Ocean. When it came to dominance in the Pacific, they knew that this would put the IJN head to head with the USN. As everyone knew, a key prerequisite to the Southern Road strategy was neutralizing the American ability to intervene in Southeast Asia, by fatally crippling the USN’s Pacific Fleet. Only the IJN could do this.
Though they did so cautiously, aware of the potential power of the United States, the IJN had been preparing for a Pacific war ever since the Washington Naval Treaty had expired in 1936. The IJN had been the third largest navy in the world since the 1920s (after those of Britain and America) and now it was growing fast. Among the large number of warships that were pouring from Japanese shipyards while the IJA was preoccupied with China and Mongolia were new, larger and better battleships and new aircraft carriers. Among the former were the Yamato class, the largest in the world, the first of which would be commissioned in December 1941. Among the latter were the Shukaku (Flying Crane) and Zuikaku (Fortunate Crane), the most modern carriers in the world, which were launched in August and September 1941, respectively.
For years, Japanese naval strategy in the Pacific – like the naval strategy of most nations – had been dominated philosophically by the theories presented by the great naval strategist Alfred Thayer Mahan in his seminal work, The Influence of Sea Power Upon History, 1660–1783, published in 1890. Mahan looked at naval strategy in terms of decisive surface battles – as had been the case in naval warfare for centuries from the battle of Salamis in 480 BC to the IJN’s own great victory at Tsushima in 1905. Japanese naval theorists had long prepared for such a decisive battle, the Kantai kessen, to take place in the Western Pacific, with the IJN having lured the USN across the ocean.
However, by 1940, another naval theorist – Admiral Isoroku Yamamoto – had come to the fore, one who advocated going deep, into the enemy’s sphere of influence, and fighting the decisive battle while on the offensive, rather fighting it on the defensive close to home. Yamamoto, who had become the commander-in-chief of the IJN Combined Fleet in 1939, was an unlikely man to occupy such a crucial position in Japan’s military hierarchy, given his long-running and contentious rivalry with Hideki Tojo, now consolidating his power at the uppermost levels of the Japanese government. Both men had been born in 1888, both had chosen military careers early on, and had risen quickly through the ranks. Both had served abroad during the 1920s, Tojo in Germany, and Yamamoto in the United States, where he attended Harvard, served as a naval attaché in Washington, and learned to speak English fluently. However, Tojo and Yamamoto had been at odds over Japanese strategic goals throughout their parallel careers, with Yamamoto being a seriously outspoken critic of both the Japanese incursion into China and of the Tripartite Pact.
Though he had deep reservations about a war with the United States, Yamamoto was the architect of implementing such a war forcefully and resolutely. Once convinced of the necessity of going to war with the Americans, Yamamoto was also able to bring Admiral Osami Nagano, chief of staff of the IJN – and a Pacific war skeptic – around to this way of thinking.
A strong advocate of naval airpower, Yamamoto’s plan was for a daring and decisive blow against the USN nearly 4,000 miles across the Pacific, at their own analog to Singapore, the great naval base at Pearl Harbor in Hawaii.
In a meeting described by John Toland, which took place at the Imperial Palace on July 31, 1941, Admiral Nagano had cautioned Hirohito about the petroleum situation. Citing figures that were somewhat more encouraging than those in the report mentioned by Tsuji, he explained that Japan’s current oil and gasoline reserves would last for 24 months, or 18 months under wartime conditions. The Dutch East Indies were essential.
“Under such circumstances, we had better take the initiative,” Nagano told the monarch, echoing Yamamoto’s strategic plan. He then added, “We will win.”
“Will you win a great victory?” Hirohito asked. “Like the Battle of Tsushima?”
“I am sorry,” the admiral admitted. “But that will not be possible.”
“Then,” Hirohito replied, “the war will be a desperate one.”
Though the window for diplomacy was nearly closed by the summer of 1941, Konoe was eager to have Nomura continue his negotiations in Washington, still holding out hope that Japan could get what it needed in Asia without a war with the United States. Nomura met with Hull, but Roosevelt was unavailable. About a week after signing Executive Order 8832, he slipped out of Washington to meet secretly with British Prime Minister Winston Churchill off the coast of Newfoundland. A USN flotilla rendezvoused with the British on August 9. Churchill arrived aboard the HMS Prince of Wales – which had been part of the task force which had run down and sunk the German battleship Bismarck a few weeks before.
The following day, the two leaders began the talks which led to the Atlantic Charter, a document which contrasted the aspirations of democracies with those of totalitarian powers. Germany was on everyone’s mind, but the two men also discussed Japan, Indochina, the Southern Road, and the likelihood of war in Southeast Asia.
As Churchill and Roosevelt had their discussions aboard the Prince of Wales, with the American battleship USS Arizona anchored nearby, nobody present could have predicted that in four months, over the space of just three days, these two formidable battleships would both be sunk – by Japanese airpower.
As Roosevelt began preparing himself psychologically for war, Prime Minister Fumimaro Konoe still held out hope for peace. Time was running out. At a meeting at the Imperial Palace on September 6, Tojo and IJA Chief of Staff Hajime Sugiyama had proposed, and Hirohito had agreed, that if diplomacy had not resolved the impasse by mid-October, Japan should move ahead with preparations for the long-anticipated war against the United States and the United Kingdom. John Toland mentions October 10 as the deadline. Postwar debriefings of Hideki Tojo have the date as October 15.
In any case, diplomacy failed to make any progress, and on October 16, Konoe submitted his resignation. Two days later, Hideki Tojo, Japan’s Minister of War, was summoned to the palace by Hirohito and asked to accept a second portfolio as Prime Minister of Japan.