The japanese road to singapore japanese perceptions of the singapore naval base, 1921 41 6

The second is the origin of operational plans to attack British Malaya and Singapore made by the Army General Staff and the Navy General Staff.. How and when did the Navy General Staff a

Chapter 3

The Origin of the Plan to Attack Singapore

1936-40

In 1936, with the termination of the Washington Treaty and its Article

19, the Imperial Japanese Navy lost its reason to accept the Singapore Naval Base Furthermore, geopolitical advantages that Japan enjoyed until then were beginning to disappear as a result of the termination of naval disarmament

treaties and technological advances This year, Japan revised the Teikoku Kokubō Hōshin (Imperial National Defence Policy), in which Britain was

included as one of its hypothetical enemies It was the first time in Japanese history that Japan formally regarded Britain as its hypothetical enemy On 11 May, when Chief of the Army General Staff, Prince Kan’in, and Chief of the

Navy General Staff, Prince Fushimi, presented the newly revised Teikoku Kokubō Hōshin, Emperor Hirohito asked: “Why add Britain?” Prince Kan’in

replied: “Recently Britain has been hastily strengthening fortifications in Hong Kong and Singapore Moreover, international relations are not stable We have

to provide against an emergency” Prince Fushimi added: “As far as the navy

is concerned, we consider it is better to avoid a war against Britain If a war against the Soviet Union should break out, the United States will join the Soviet side If a war against the United States should break out, the Soviet Union will join the American side In these cases, China will definitely join

our enemy If Britain also joins our enemy, we stand no chance of winning On the other hand, if a war against Britain should break out, there will be a high possibility that not only China but also the United States and the Soviet Union will join our enemy It is better to avoid these scenarios by diplomacy The reason why we added Britain is to provide against an emergency and no more than that.”1 But five years later, Japan plunged into war against Britain and the United States by attacking British Malaya, the Philippines and Hawaii simultaneously

When considering Japanese policies against Britain in the period between the two world wars, 1936 was an important turning point On 15 January, the Japanese government announced withdrawal from the London Naval Conference On 26 February, there was the 26 February Incident, which was an attempted military coup d’état In the early hours of the morning, soldiers led by radical junior-echelon army officers, attacked government buildings in Tokyo Several senior politicians were murdered The Prime Minister, Okada Keisuke, narrowly escaped being murdered The Emperor, believing the Prime Minister had been killed, ordered the Imperial Japanese Army to suppress them After the 26 February Incident, Hirota Kōki formed a

new cabinet on 9 March The revision of the Teikoku Kokubō Hōshin was

approved on 3 June On 7 August, the Hirota Government adopted

“Fundamentals of National Policy (Kokusaku no Kijun)” in which the

Japanese government stipulated expansion to both the south and the north The south-bound policy was officially approved as a national policy On 25 November, it concluded the German-Japanese Anti-Comintern Pact.2

This chapter examines the Japanese south-bound policies from 1936

to 1940 and the origin of the Japanese plan to attack British Malaya and Singapore In particular, it analyses the history of two different but related aspects The first is why the Imperial Japanese Navy proposed the south-bound policy and how it became national policy The second is the origin of operational plans to attack British Malaya and Singapore made by the Army General Staff and the Navy General Staff How and when did the Navy General Staff and the Army General Staff make their first operational plans to attack British Malaya and Singapore? It has been widely believed in the English-speaking world that Japan had been preparing to attack British Malaya and Singapore for many years On the other hand, some historians considered that Japan made the plan to attack Singapore from scratch just before the war.3Both of these views should be reconsidered

2 Kiyoshi Ikeda, “The Road to Singapore: Japan’s View of Britain, 1922-41”, in Fraser, T.G and Lowe, Peter (eds.), Conflict and Amity in East Asia: Essays in Honour of Ian Nish (Basingstoke: Macmillan Press, 1992), p.31

3 Haruo Tohmatsu, “The Imperial Army Turns South: the IJA’s Preparation for War against Britain, 1940-1941”, in Ian Gow, Yoichi Hirama and John Chapman (eds.), The History of Anglo-Japanese Relations, 1600-2000 Volume Three: The Military Dimention (Basingstoke: Macmillan Press, 2003), p.176; Brian P Farrell, The Defence and Fall of Singapore 1940-1942 (Stroud:

Tempus, 2005), p.107

The Origin of the South-bound Policies

The origin of Japanese south-bound military policies can be traced back to 1933 Before that, Japanese south-bound movements did not assume a military tone As early as the early Meiji period, in the 1870s and 1880s, the

Japanese started living as immigrants in Nanyo The Japanese word Nanyo

referred to islands in the south Pacific, and islands and islets in Southeast Asia

in the Meiji Period4, but from around the time of the First World War, it was enlarged to refer to islands in the south Pacific and the region that we currently

know as Southeast Asia Soto Nanyo or Omote Nanyo referred to Southeast Asia while Uchi Nanyo or Ura Nanyo referred to islands in the south Pacific.5

After the Russo-Japanese War, some of the leading Admirals, such as Yamamoto Gombei and Satō Tetsutarō, envisaged south-bound advance as future national policy They considered south-bound advancement would be more beneficial for national defence and development than the army’s north-bound expansion into Manchuria and Mongolia But their expectations

in the south were too vague to be formed into a concrete naval policy.6 During

4 From 8 August 1868 to 30 July 1912

5 Hajime Shimizu, Southeast Asia in Modern Japanese Thought: Essays on Japanese-Southeast Asian Relationship 1880-1940 (Nagasaki: Nagasaki Prefectural University, 1997), p.4 ; Sumio Hatano, “Kokubō Kōsō to

Nanshin-ron (National Defence Policies and South-Bound Policies)”, in

Yano,Tōru, Tōnan Ajia to Nihon (South East Asia and Japan) (Tokyo: Kōbundō, 1991), p.149

6 Kiyoshi Ikeda, “The Road to Singapore: Japan’s View of Britain, 1922-41”, p.35; Ken’ichi Goto, Shōwa ki Nihon to Indonesia (Japan and Indonesia in Shōwa Era) (Tokyo: Keisō Shobō, 1986), p.20; Sumio Hatano, “Nihon Kaigun to Nanshin Seisaku no Tenkai (The Japanese Navy and its Policies to the South”

in Shinya Sugiyama and Ian Brown (eds.) Senkan-ki Tōnan Ajia no Keizai Masatsu: Nihon no Nanshin to Ajia Ōbei (Economic Frictions in South East Asia during the Inter War Period: Japanese South-bound Policies, Asia and Western Powers (Tokyo: Dōbunkan Shuppan, 1990), p.142

the Taishō Period7, Japanese companies sought economic expansion in Nanyo

Trading companies and banks established their branches in Singapore As a

result, there was a sharp rise in Japanese exports to the Nanyo region However, the Imperial Japanese Navy had no military policy for the Nanyo region From

the Japanese point of view, Japanese south-bound advancement did not contradict the colonial policies of Western powers because the Japanese had no

intention to overthrow Western interests in Nanyo It was not until the middle

of 1933－after Anglo-Japanese relations were deteriorating in consequence of Japanese military actions in Manchuria in 1931, the Shanghai Incident in 1932, the Japanese proclamation of Manchukuo on 1 March 1932 and the Japanese withdrawal from the League of Nations in 1933－that the Imperial Japanese Navy began to examine a policy of advancing into the south In September

1933, when a Japan-India-Britain conference on the cotton trade had been deliberating in Simla, which intensified anti-British feeling in the Japanese public, the Minister of the Navy, Ōsumi Mineo, approved a “Guideline dealing with China” which stipulated: “Faced with the military penetration by the powers into the south of China, Japan must be more intensively watchful of them, and try to prevent their aggressive moves It is now inevitable for Japan

to adopt a more active strategy in this area within the very near future.”8 A historian, Ikeda Kiyoshi, pointed out that it was the first formal announcement

7 From 30 July 1912 to 25 December 1926

8 Ikeda “The Road to Singapore: Japan’s View of Britain, 1922-41”, p.36; Gendaishi Shiryō (Documents on Modern History), Vol 8, Nitchū Sensō 1 (Sino-Japanese War 1) (Tokyo: Misuzu Shōbō, 1964), p.10, pp.351-53

of south-ward advance made by the navy.9 But at that time, south-ward advance meant advance to southern China There was no military plan for

advancing to the Nanyo region

Economic reasons lay behind why the Imperial Japanese Navy

aroused interest in Nanyo in the mid-1930s A historian, Asada Sadao, wrote:

“As long as Japan could obtain such resources as petroleum, rubber, and scarce metals through trade with the United States and the western colonial powers in Southeast Asia, the navy did not need to intervene However, as relations with the United States deteriorated, the navy became increasingly concerned with the possible shortage of petroleum for its fleets and naval aviation.”10 Another historian, Goto Ken’ichi, pointed out that one of the two reasons why the Imperial Japanese Navy did not have a south-bound military expansion policy until the mid-1930s came from its oil supplying policy.11Since the time of the First World War, the Imperial Japanese Navy’s policy consisted of two parts The one was a self-support programme and the other was an oil import programme However, in 1916, it had already become clear that it was impossible to self-support its oil consumption In 1917, it contracted an agreement with the Anglo Petroleum Company to import oil from Tarakan, Borneo This contract solved the navy’s oil supply problem In later years, the contract to import Borneo oil was succeeded by the Asiatic

9 Ikeda, “The Road to Singapore: Japan’s View of Britain, 1922-41”, p.36

10 Sadao Asada, From Mahan to Pearl Harbor: The Imperial Japanese Navy and the United States (Annapolis: Naval Institutional Press, 2006), p.207

11 The other reason was pro-Anglo-American policies pursued by the “treaty faction” of the Imperial Japanese Navy

Petroleum Company.12 As long as the import of oil was secure by free trade, it did not require a policy of forcefully capturing oil In other words, importing

oil from Nanyo put the brakes on a naval south-bound military policy until the

mid-1930s What was important for the Imperial Japanese Navy until the

mid-1930s was how to secure a stable supply of oil from Nanyo by

importation.13 South-bound military advancement to Nanyo was incompatible

with this policy However, as relations with the United States and Britain were deteriorating, importing oil from Southeast Asia became uncertain

To research the Nanyo region, the Imperial Japanese Navy established

on 15 July 1935 the Committee to Investigate Southern Policy, with the Vice-Chief of the Navy General Staff, Shimada Shigejirō, as the chairman Members of this committee consisted of officers of the Ministry of the Navy and the Navy General Staff Commander Chūdō Kan’ei and Captain Nakahara Yoshimasa proposed establishing this committee to Captain Oka Takazumi and

it was established on Oka’s initiative Chūdō and Nakahara had developed a

passionate interest in Nanyo through books and voyages.14 Chūdō realised

during a graduate voyage of the Naval Academy to Nanyo in 1916 that only a

small number of Western people exploited rich natural resources in

undeveloped Nanyo Consequently, there would be great opportunities for the

Japanese to develop industries and foster trade in this region The Imperial Japanese Navy could back up their activities by financial aid, giving

12 BBKS, Senshi Sōsho: Kaigun Gunsenbi, 1 (Naval Armament and War Preparations, Vol 19) (Tokyo: Asagumo Shinbunsha, 1969), pp.694-95

13 Goto, Shōwa ki Nihon to Indonesia, 22-31, pp.83-85

14 Hatano, “Nihon Kaigun to Nanshin Seisaku no Tenkai”, p.149

intelligence, and protecting sea routes Nakahara, who had a nickname “The

King of Nanyo”, shared similar experiences.15 The main purpose of the committee was to research the oil question For the first time, the Imperial Japanese Navy began to systematically investigate petroleum resources in the

Nanyo region, especially in the Dutch East Indies, in order to prepare for a

Japanese-American conflict The aims of the committee included conducting

various surveys and studies of everything related to Omote Nanyo－British

Malaya, Borneo, the Dutch East Indies and French Indochina－from the viewpoints of national defence and the national policy relating to it Commander Nakazawa Tasuku, a member of this committee, was of the opinion that any advance to the East Indies might very well result in a clash with the Anglo-American powers However, in this committee’s study, as

regards an advance on Omote Nanyo, the Imperial Japanese Navy did not

necessarily play a primary role, economic expansion or immigration were the basic methods studied.16 In other words, at this stage, Nanshin (South-bound Advancement) to Nanyo did not mean military expansion

After Hirota Kōki formed a cabinet on 9 March, to study and formulate naval policies, the Ministry of the Navy established three new committees on 19 March Members of these committees consisted of officers

of the Ministry of the Navy and the Navy General Staff Their aim was “to prepare naval armaments that will give confidence in national defence in view

of the fact that at the end of this year [1936] naval treaties will expire”.17Among these three committees, the most important for our purpose was the First Committee The task of the First Committee was to study and formulate a firm and concrete policy of south-bound expansion The Second Committee was to study how to make the organisation of the Imperial Japanese Navy more efficient and the Third Committee was to study naval budget and financial affairs The Chair of the First Committee was Vice-Admiral, Toyoda Seomu, Chief of Naval Affairs Bureau However, it has been said that the officer who actually dominated the First Committee was Captain Nakahara Yoshimasa who was the foremost exponent of a south-bound advancement within the Imperial Japanese Navy Policies set forth by the First Committee

were summarised in the paper “National Policy Guidelines (Kokusaku Yōkō)”

with army’s policies on the continent in April 1936 It stipulated: “The basic policy of imperial national policy guidelines should be to reinforce various policies domestically while securing a foothold for the Empire on the continent and simultaneously expanding southwards”.18 With regard to policy towards the “various southern countries”, it insisted on:

Kōronsha, 2002), pp.123-24; BBKS, Senshi Sōsho, Daihon’ei Rikugunbu, 1 (Imperial Headquarters, Army, Vol.1, Up to May 1940)’(Tokyo: Asagumo Shinbunsha, 1967), p.381; Ikeda, “The Road to Singapore: Japan’s View of Britain, 1922-41”, pp.36-37

Domestically, a method which will permit unification [of making and execution of policies] should be discussed and determined; and the necessary organisations established, while the administration of Taiwan and the Mandated Islands should be strengthened Internationally, a gradual expansion should be attempted, for the time being, through increasing immigration and economic expansion, while careful preparations shall constantly be made against pressure or interference from Britain, the United States and the Netherlands, which is naturally to be expected The completion of preparations of forces, for an emergency, is necessary.19

This paper stipulated increasing immigration and economic expansion

as means for Japanese south-bound policies but also anticipated the situation that Britain and the Netherlands would become possible enemies The United States remained the main target of the naval expansion.20 The Imperial Japanese Navy’s policies for Britain and the United States were outlined in the National Policy Guidelines as follows:

Policies Towards Britain

Great caution must be paid to possible action by Britain to use another foreign power, in particular the United States, the Soviet Union or China, to apply pressure on Japan, and we must take advantage, whenever possible, of the delicate political situation in Europe and the political condition in the British colonies in order to expand our national power into the cracks among

19 Ibid

20 Asada, From Mahan to Pearl Harbor, p.207

British interests in East Asia Furthermore, economic and cultural ties with British possessions shall be intensified, in order to check their anti-Japanese policies

Policies Towards the United States

In order to oppose the traditional Far Eastern policy of the United States, armaments shall be held at a satisfactory level, the United States’ approval

of the Japanese Empire’s status in East Asia shall be sought, and the establishment of a friendly relationship, based on economic interdependence, shall be also sought.21

In the National Policy Guidelines, a historian, Aizawa Kiyoshi, points out: “the stance towards Britain was more confrontational and challenging than the stance adopted towards the United States”22 However, it neither anticipated military confrontation against Britain, nor advocated military advancement to the south It could not be regarded as a harbinger of attacking Singapore

The more urgent reason why the Imperial Japanese Navy laid out its south-bound policy at the time was to counter the Imperial Japanese Army’s

Hokushin Nanshu Ron (Advance to the North, Hold in the South Policy) for

preventing a situation that the budget for the navy would be snatched by the

21 Gendaishi Shiryō Dai 8 kan, Nitchū Sensō 1, pp.354-355; Aizawa, “The Path Towards an ‘Anti-British’ Strategy by the Japanese Navy between the Wars”, p.143

22 Ibid

army On 1 August 1935, the army officer, Colonel Ishihara Kanji, who was the mastermind of the Manchuria incident, became Chief of Operations Section of the Army General Staff He concluded that preparations for war against the Soviet Union, which he thought would break out in the near future, were unsatisfactory He considered the Army General Staff would make unified national policy with the Navy General Staff to confront the Soviet Union by strengthening Manchukuo and seeking co-operation with China Accordingly, he started negotiations with his naval counterpart, Captain Fukudome Shigeru, on 17 December 1935.23 In these negotiations, Ishihara told Fukudome: “In the next ten years, what Japan has to do is to strengthen Manchukuo Japan has no strength to implement other policies It will not be too late to frame the south-bound policy after that.”24 However, Ishihara’s plan which took strengthening Manchukuo and army’s preparations for war against the Soviet Union as priority was not acceptable to the navy The navy also had to strengthen its armaments in view of the fact that at the end of 1936 naval disarmament treaties would expire Furthermore, the navy looked disapprovingly at what the army did in Manchuria and northern China The navy considered it had to prevent the army’s war against the Soviet Union and present a counter plan Commander Takada Toshitane, a member of the First Committee at that time, recollected after the war that the prime aim of the First

23 BBKS, Senshi Sōsho: Daihon’ei Kaigun-bu: Rengō Kantai 1., p.290

24 Shigeru Fukudome, “Hogo ni Kishita Teikoku Kokubō Hōshin (Throwing National Defence Policy into the Wastebasket)” in Chisei, Bekkan, Himerareta Showa Shi (Intellectuals, Supplementary Volume, Secrets in Showa History) (Dec, 1956), pp.176-177

Committee was to propose counter plans to the army from the naval side.25 In the National Policy Guidelines, the Imperial Japanese Navy proposed a

Hokushu Nanshin Ron (Hold in the North, Advance to the South Policy) by

stating “the basic policy of imperial national policy guidelines should be to reinforce various policies domestically while securing a foothold for the Empire on the continent and simultaneously expanding southwards”.26

The Hirota Government, which was unable to decide on priority between the army’s plan to the north and the navy’s plan to the south, settled

on a compromise between the two armed forces on 7 August 1936 at the Five Ministers’ Conference which consisted of the Prime Minister, the Minister of Foreign Affairs, the Minister of Finance, the Minister of the Navy and the

Minister of War It was the famous “Fundamentals of National Policy (Kokusaku no Kijun)” which stipulated expansion towards both the south and

the north.27 This showed the fact that the government could not co-ordinate the contradictory policies of the Imperial Japanese Navy and the Imperial Japanese Army What the government did was to formulate bureaucratic compromising policies as the “Fundamentals of National Policy” which incorporated incompatible policies enacted by two armed forces separately For the navy, enactment of “Fundamentals of National Policy” was a success

in “Defence against the army” preventing a situation where the budget for the

25 BBKS, Senshi Sōsho: Daihon’ei Kaigun-bu: Rengō Kantai, 1., pp.290-300.

26 Aizawa, “The Path Towards an ‘Anti-British’ Strategy by the Japanese Navy between the Wars”, p.142

27 Gendaishi Shiryō Dai 8 kan, Nitchū Sensō 1, pp.361-62

navy would be snatched by the army by stipulating the south-bound policy.28The army also succeeded in stipulating its assertion to the north By adapting

the “Fundamentals of National Policy”, the two armed forces justified the

expansion of their budgets and armaments Hirota explained to Tōgō Shigenori after the war in Sugamo Prison, “I considered that the real aim of the

“Fundamentals of National Policy” was to justify expansion of the budget of the two armed forces and no more than that The navy justified fleet expansion after the naval treaties expired The army also took advantage of the opportunity [to expand its budget].”29 Consequently, “Fundamentals of National Policy” expressed a policy of gradual advance to the south, especially

to the Soto-Nanyo (Southeast Asia) region, through peaceful means In this

way, the south-bound expansion policy was formulated officially as a national policy in 1936 What is important is that the Japanese government failed to formulate either strategic priority, or coordinated military policy between the two armed forces “Fundamentals of National Policy” stated that:

Japan expects its national and economic advance into the south, especially

into Soto-Nanyo areas through gradual and peaceful means, with avoiding

hostilities with other countries in order to consolidate its national and economic power as well as strengthening of Manchukuo.30

28 BBKS, Senshi Sōsho: Daihon’ei Kaigun-bu: Rengō Kantai, 1., p.290

Vice-Admiral Oka Takazumi used the term “Defence against the army” in an interview by Nomura Minoru on 9 April 1963

29 Shigenori Tōgō, Jidai no Ichi Men (An Aspect of Showa Era) (Tokyo:

Kaizōsha, 1952), p.98

30 Gendaishi Shiryō Dai 8 kan, Nitchū Sensō 1, pp.361-62

As for naval armament, it said: “The aim of naval armament is to establish enough power to secure command of the western Pacific against the United States Navy.”31 What aroused our interest is that, even though

“Fundamentals of National Policy” proclaimed south-bound economic expansion, the target of the build up of naval armaments was still the United States Navy

Revising Teikoku Kokubō Hōshin

As we saw in Introduction and Chapter 1, the Teikoku Kokubō Hōshin

was first sanctioned in 1907 as a post Russo-Japanese War defence policy This was revised in 1918 and 1923 Until the 1936 revision, the hypothetical

enemies mentioned in the Teikoku Kokubō Hōshin were the United States,

Russia (the Soviet Union), and China The Imperial Japanese Army regarded the Soviet Union and China as its hypothetical enemies while the Imperial Japanese Navy regarded the United States as its hypothetical enemy The listing of Britain as one of the hypothetical enemies alongside the Soviet

Union, the United States and China in the 1936 revision of the Teikoku Kokubō Hōshin was undertaken on the initiative of the Navy General Staff Captain

Fukudome Shigeru, Chief of the Operations Section of the Navy General Staff, recollected after the war that “it had become impossible to leave Britain and

31 Ibid

the Netherlands out of our calculations as hypothetical enemies, aside from the United States, the Soviet Union and China, which had heretofore been our hypothetical enemies”.32 Commander Nakazawa Tasuku, a member of the Operations Section of the Navy General Staff and the navy’s representative to

the group that actually drafted the revisions of the Teikoku Kokubō Hōshin,

pointed out five reasons why they added Britain to the hypothetical list:

(1) Britain contributed greatly to Peace in the Far East by the Anglo-Japanese Alliance for a long time, from 1902 to 1921 However, with the conclusion of the Washington Treaty, the Anglo-Japanese Alliance was abrogated and the Four Power Treaty was enacted;

(2) after the abrogation of the Anglo-Japanese Alliance, Britain established greater intimacy with the United States;

(3) after the Manchuria Incident, British attitude toward Japan had deteriorated and Anglo-American relations became inseparable;

(4) if Japan executed its policy in the continent, there was a high possibility that Britain and the United States would be obstacles to Japan; and (5) if Japan adopted a southern advance policy and carried out an economic expansion into the Dutch East Indies, it was to be expected that the Netherlands would depend on Britain and harden their anti-Japanese attitude.33

32 Fukudome, “Hogo ni Kishita Teikoku Kokubō Hōshin”, p.176; Aizawa, “The Path Towards an ‘Anti-British’ Strategy by the Japanese Navy between the Wars”, p.143

33 Nakazawa Tasuku Kankō Kai (ed), Kaigun Chūjō Nakazawa Tasuku:

What is interesting for us is that he did not mention the Singapore Naval Base in these five reasons This backs up the view this thesis presented

in Chapter 1 that the Imperial Japanese Navy did not consider the Singapore Naval Base as an imminent threat in the 1920s

After the Russo-Japanese War, especially after the Washington Conference in 1921/22, the United States was the Imperial Japanese Navy’s only hypothetical enemy In fact, as we saw in Chapter 1, various naval armament plans were only aimed at the United States until the mid-1930s However, as a result of a consequence of situations in the mid-1930s, there appeared a possibility for the Imperial Japanese Navy that, if Japan carried out expansion to the south, even though it would be economic expansion, Britain would become a confronting power to Japan The German Naval Attaché in Tokyo, Paul Wenneker, described the change in the Imperial Japanese Navy in June 1936 as follows:

I was able to confirm, to my surprise that, by contrast with the period of more than six months before, when the whole Japanese Navy had still, as much as ever, seemed to be fixed intently and unflinchingly on the United States as its only future opponent, of late a fundamental change in this attitude has come about even among front-line units In the front line, they actually advocate an even tougher line than the Ministry of the Navy itself, Sakusen Buchō, Jinji Kyokuchō (Vice-Admiral Nakazawa Tasuku, Chief of the Operations Division and Personnel Bureau) (Tokyo: Hara Shobō, 1979), p.14

from which the influence in this direction undoubtedly stems and where I have for sometime past been observing the phenomenon The United States

is no longer regarded exclusively as the future enemy, but now it is primarily Britain It is practically certain that operational investigations are being conducted against a fleet attacking from the south-west－Singapore.34

There is no evidence that the Imperial Japanese Navy anticipated a British attack from Singapore at that time, but Wenneker recognised the abrupt change of atmosphere among the younger generation of naval officers

Advocates of South-bound Policies

In 1936, Commander Ishikawa Shingo, then a staff officer of the Second Fleet, made a fact-finding tour to Europe On his way to Europe, he visited the Philippines, Java, Sumatra and Singapore In the summer of 1941,

he took a leading role to establish a consensus among middle-echelon naval officers that war against the United States and Britain was unavoidable Before this tour, he had strong anti-American feelings, but he had no interest in

Southeast Asia In 1931, he published a book Nihon no Kiki (Crisis of Japan)

under the pen name of Ōtani Hayato, in which he expressed his opinion that Japan would fight a war against the United States over interests in Manchuria, but he did not mention advancement to Southeast Asia or a clash with Britain

34 Aizawa, “The Path Towards an ‘Anti-British’ Strategy by the Japanese Navy between the Wars”, p.144

in this book.35 However, after returning from this tour, he became a strong advocate of south-bound expansion

Ishikawa looked back on this tour in his book published in 1960, in which he stated that he had an impression that an ABCD (American, British, Chinese and Dutch) encirclement was in the making to the south of Japan In Java, he recognised that the Dutch authorities in the Dutch East Indies kept strict watch on him In Singapore, he was impressed by the number of oil tanks He estimated from the size and number of oil tanks that Britain stored at least a half of million tons of oil in Singapore Considering that Britain could also be backed up with oil fields in Sumatra, he realised, if a war should break out, it was suitable for Britain to use Singapore as the base for long-term operations He wrote in the book: “I observed that the British intention to build

a huge base here [in Singapore] was very serious The influence of the base spread over the South China Sea, Indochina and the Dutch East Indies It also could work in concert with American bases in Hawaii and the western Pacific Consequently these bases could overwhelm Japan without difficulty The Washington Treaty prohibited Japan from establishing bases in the Bonin Islands and Omami Oshima but allowed Britain to build such a huge base in Singapore The treaty advocated World peace but actually it just forcefully oppressed Japan.” On the day of leaving Singapore, he was investigated by the British authorities At the place of investigation, a Dutch officer sat with British officers and they asked what Ishikawa did, not only in Singapore, but

35 Hayato Ōtani, Nihon no Kiki (Crisis of Japan) (Tokyo: Moriyama Shoten, 1931)

also in the Dutch East Indies From these experiences in Singapore, he speculated that Britain and the Netherlands had made some kind of a secret agreement.36 In Europe, he realised the rise of Germany and the decline of Britain as world powers

On his return from his tour, Ishikawa presented his report to naval leaders, including the Minister of the Navy, Nagano Osami He expressed his personal views in this report: “As the influence of the Japanese Empire advances, Anglo-Japanese conflicts shall become inevitable”37 As for the

Nanyo region, he advocated demanding Open Door Policies for the Straits

Settlements, British and Dutch East Indies, the Philippines, Australia and the New Zealand, which meant Britain and the Netherlands should open their trade doors to the Japanese The three main points of the report were as follows First, an ABCD (American, British, Chinese and Dutch) encirclement was in the making to the south of Japan Second, Japan could count on Germany which would rise up in arms around 1940 Ishikawa predicted that it would be a golden opportunity for Japan to break through this ABCD encirclement Third, before 1940, it would be premature to rise up in arms However, the reaction of the naval leaders to the Ishikawa’s report was chilly

36 Shingo Ishikawa, Shinjuwan made no Keii: Kaisen no Shinsō

(Circumstances Leading to Pearl Harbour: The Truth about the

Commencement of the War) (Tokyo: Jiji Tsūshinsha, 1960), pp.110-113

37 “0257, Teikoku no Tōmen suru Kokusai Kikyoku Dakai-saku Shian

(Personal Views on Challenging International Situation the Empire Faces)” in Institute of Oriental Studies, Daito Bunka University (ed.), Shōwa Shakai Keizai Shiryo Shūsei: Dai 2, Kaigun Shō Shiryō (2) (Documents of Society and Economy in Shōwa Period, Vol 2, Documents of the Ministry of the Navy (2)) (Tokyo: Institute of Oriental Studies, Daito Bunka University, 1980), p.286

He wrote that no one showed any interest in it.38 His fears and anxieties were premature for several years and in 1936 only existed in Ishikawa’s imagination

In spite of his ambition to work in Tokyo, he was sent back to work at sea as

captain of the tanker, Shiretoko At that time, Ishikawa’s view was too radical

for naval leaders to accept.39

On 3 September, a great opportunity came for south-bound advocates within the Imperial Japanese Navy A Japanese national was murdered by a Chinese thug in Peihai on the coast of Kwangtung The Navy’s Third Fleet stationed in China dispatched a group of vessels to demonstrate its aggressive attitude Facing the incident, Captain Nakahara Yoshimasa, then a staff officer

of the Navy General Staff, advocated the occupation of Hainan Island, lying off French Indochina and rich in iron ore He wrote in his diary, “To change the situation radically, there remains nothing but to face down Britain Thus the occupation of Hainan! We should occupy Hainan while Britain is unprepared”.40 However, the occupation of Hainan Island did not materialise because of opposition from senior naval leaders.41 But this episode showed how radical middle-echelon officers who advocated south-bound policy regarded Britain at that time Their perceptions of Britain were different from those held by senior officers

As we saw above, as a younger generation naval officer who did not

38 “0257, Teikoku no Tōmen suru Kokusai Kikyoku Dakai-saku Shian”, in Shōwa Shakai Keizai Shiryo Shūsei: Dai 2, pp.286-291; Ishikawa, Shinjuwan made no Keii: Kaisen no Shinsō, pp.122-23

39 Goto, Shōwa ki Nihon to Indonesia, p.47

40 Ikeda, “The Road to Singapore: Japan’s View of Britain, 1922-41”, p.37

41 Ikeda, “The Road to Singapore: Japan’s View of Britain, 1922-41”, p.37; Asada, From Mahan to Pearl Harbor, p.209

participate in discussions over naval disarmament in the 1920s, Ishikawa’s view on relations between the Singapore Naval Base and the Washington Treaty was different from those of senior generation who had participated in the discussions From the mid-1930s to the outbreak of war in 1941, south-bound policies were advocated by younger generation represented by Ishikawa Shingo, Nakahara Yoshimasa and Chūdō Kan’ei They entered the Imperial Japanese Navy in the 1910s and spent junior officers’ years at sea in the 1920s They might be influenced by anti-Anglo-American public opinion

in the 1920s outside of decision making processes of the navy In the 1930s, these officers started working in the Ministry of the Navy or the Navy General Staff as junior or middle echelon officers Traditionally, the Imperial Japanese Navy had been under the strong influence of Britain and the Royal Navy By the mid-1930s, however, younger naval officer’s views of Britain became more similar to those of ordinary Japanese

With the adoption of several policies in 1935 and 1936, the Imperial Japanese Navy’s south-bound advance policies entered a new stage With the introduction of “Fundamentals of National Policy”, the south-bound policy became official national policy Within the Imperial Japanese Navy, there appeared advocates of south-bound expansion such as Ishikawa Shingo and Nakahara Yoshimasa Later, in the summer of 1941, Ishikawa Shingo took a leading role in establishing a consensus among middle-echelon officers that war against the United States and Britain was unavoidable.42 However, it is

42 Asada, From Mahan to Pearl Harbor, pp.250-269

wrong to overestimate the introduction of this policy and the influence of radical middle-echelon officers At that time, the Imperial Japanese Navy had

no military plan against the Nanyo region and views expressed by radical

middle-echelon officers were rejected by their superiors What the Imperial Japanese Navy considered was that, if Japan advanced to the south economically, there would be a possibility that Britain would become a confronting power for Japan It is wrong to consider, however, that at this stage the Imperial Japanese Navy regarded an Anglo-Japanese military confrontation as inevitable In 1935/36, it did start examining the possibility of waging war against Britain, but it was considered no more than a remote possibility

Evolution of Operation Plans to Attack Singapore 1936-1940

As we saw above, from around 1935 to 1936, Japan started

considering south-bound policies against the Nanyo region, but until 1939

there was no substantial operational plan for British Malaya and Singapore In this section, we trace the origin and evolution of operational plans for attacking British Malaya and Singapore in Annual Operational Plans The Army General Staff and the Navy General Staff made and presented their Annual Operational Plans against each hypothetical enemy stipulated in the

Teikoku Kokubō Hōshin annually to the Emperor and received approval for

them Annual Operational Plans for the next financial year were made by

members of the Operations Sections of the General Staffs usually in summer43

In peace time, they were used for establishing military or naval policies on armaments, formations, manoeuvres, education, communications and intelligence If war should break out, the Army General Staff and the Navy General Staff composed Imperial General Headquarters and made its operational (war) plan based on the Annual Operational Plans

In 1936, Britain was first included in the hypothetical enemy list in

the Teikoku Kokubō Hōshin In August that year, the Navy General Staff

included its first operational plan against Britain in its “Annual Navy’s Operational Plan for 1937” However, this plan simply stipulated without detail, “the navy will annihilate British fleet in East Asia, bring East Asia seas under its control, and destroy British bases in cooperation with the army”44 There was no description of how to attack, where to attack, and how many forces would be required for the attack It was “Operational Plan” without any operational plan But it is natural to suppose that “British bases” meant Singapore and Hong Kong According to Nakazawa Tasuku, a staff officer of the Operations Section, the Navy General Staff lacked information on British Malaya and British Borneo, so it could not make a detailed plan.45 Meanwhile, the Army General Staff, which also had scarce information about Southeast Asia with which to make an operational plan, dispatched its staff officer, Major Arisue Yadoru, who had just returned from Britain where he had been

43 Japanese financial year is from April to March

44 BBKS, Senshi Sōsho: Daihon’ei Kaigun-bu, 1 , p.350

45 Ibid

stationed as the Military Attaché, to Hong Kong and Singapore to gather information.46

The Sino-Japanese War started at Marco Polo Bridge on 7 July 1937

On 13 August, the war spread to Shanghai, the centre of the British sphere of interest in China On 20 November, Imperial General Headquarters was established In December, Japan occupied Nanjing but the Chinese Nationalists did not surrender Faced with stronger resistance than anticipated, the Japanese turned their eyes on Britain and the Soviet Union as the backers

of the Chinese Nationalists Robert Craigie, then the British Ambassador to Japan, found anti-British feelings “still very strong even in naval circles” in the spring of 1938 and at the end of the year he reported that the “Japanese Navy－and particularly in its younger officers－are manifesting such strong anti-British sentiments.”47 In September 1938, Captain Yokoi Tadao, a staff officer of the Operations Section of the Navy General Staff, wrote a paper entitled, “Why Anti-British Feeling Rising?” In this paper, he argued that the direct reason for deteriorating Anglo-Japanese relations was that, even though Britain declared neutrality, Britain backed up the Chinese Nationalists in the Sino-Japanese War In this paper, he pointed out several indirect reasons such

as the abrogation of the Anglo-Japanese Alliance and the 5:5:3 capital ship’s ratio at the Washington Conference But he did not mention the Singapore

46 BBKS, Senshi Sōsho: Daihon’ei : Daihon’ei Rikugunbu, 1, p.416

47 TNA, FO 371/21521; ADM1/9909, Craigie to Foreign Office”, dated on 7 May 1938, “Craigie to Halifax, dated on 14 December 1938, cited in Marder A., Old Friends, New Enemies, (Oxford: Clarendon Press, 1981), 25; Ikeda, “The Road to Singapore: Japan’s View of Britain, 1922-41”, p.39

Naval Base.48 These views among younger officers were not their original As

we saw in the previous chapter, the commercial publishing media advocated similar opinions As anti-British opinion arose in the Japanese public, anti-British feeling among middle-echelon naval officers grew in 1938 In February 1939, Japan occupied Hainan Island

Because of the outbreak of the Sino-Japanese War, the Operations Sections could not make their Annual Operational Plans for 1938 during 1937 Without any perspective on the course of the Sino-Japanese War, they could not establish any plan Since January 1938, after the protraction of the Sino-Japanese War became clear, Commander Yamamoto Chikao from the Operations Section of the Navy General Staff and Captain Imoto Kumao from the Operations Section of the Army General Staff had negotiated for co-ordinating their Annual Operational Plans for 1938 between the two armed forces In June, Yamamoto Chikao and Imoto agreed to each make operational plan which would suppose the situation that Britain would enter the Sino-Japanese War on the Chinese side They agreed that the enemy’s positions they should mention in their operational plans as attacking targets were Hong Kong, British Borneo, British Malaya, and Singapore They paid attention to the situation that, even though the number of British forces had not increased from the previous year, the Singapore Naval Base was almost completed and, since the outbreak of the Sino-Japanese War, Britain had been

48 Shōwa Shakai Keizai Shiryo Shūsei: Dai 6 kan, Kaigun Shō Shiryō (6) (Documents of Society and Economy in Shōwa Period, Vol.6, Documents on the Ministry of the Navy (6)), (Tokyo: Institute of Oriental Studies, Daito Bunka University, 1983), pp.133-141

rapidly strengthening fortifications as well as airfields in Singapore and Hong Kong.49 Singapore first appeared in two operations plans in the “Annual Navy’s Operational Plan for 1938” which were made in August 1938: in the Operations Plan against Britain and China, and in the Operations Plan against four countries: the United States, Britain, the Soviet Union and China In this plan, the Navy General Staff first made its operational plans which assumed the situation that Japan would fight against more than two enemies However, they were still “Operational Plans” without any substantial operational plan There was no description on how to attack and how many forces would be required for attack Also the operational plan against the four countries was just a combination of each operational plan against each country without any adjustment The operational plans against Britain in the operational plans against China and Britain and those in the plans against four countries were identical There was no integrated operational plan against four.50

The first substantial operational plans for attacking Singapore were included in the “Annual Navy’s Operational Plan for 1939” and the “Annual Army’s Operational Plan for 1939”, which were presented to the Emperor in February 1939 What arouses our interest is the landing sites in the Malay Peninsula stipulated in them The “Annual Army’s Operation Plan for 1939” and “the Annual Navy’s Operations Plans for 1939” included a plan for landing in Singora in Thailand or in Mersing in British Malaya The necessity

of landing in Singora in Thailand was advocated by the Army General Staff for

49 BBKS, Senshi Sōsho: Daihon’ei Kaigun-bu, 1 , p.370, 376

50 Ibid., pp.376-378