Nanshin-ron
was a political doctrine in the Empire of Japan that stated that Southeast Asia and the Pacific Islands were Japan's sphere of interest and that their potential value to the Empire for economic and territorial expansion was greater than elsewhere.
The opposing political doctrine was, largely supported by the Imperial Japanese Army, which stated the same but for Manchuria and Siberia. After military setbacks at Nomonhan, Mongolia; the start of the Second Sino-Japanese War tying down millions of Japanese troops in China; and negative Western attitudes towards Japanese expansionist tendencies, the Southern Expansion Doctrine became predominant. Its focus was to procure resources from European Southeast Asian colonies, eliminate supply routes to China, and neutralize the Allied military presence in the Pacific. The Army favored a "counterclockwise strike", while the Navy favored a "clockwise strike".
Meiji-period origin
In Japanese historiography, the term nanshin-ron is used to describe Japanese writings on the importance to Japan of the South Seas region in the Pacific Ocean. Japanese interest in Southeast Asia can be observed in writings of the Edo period.After the Meiji Restoration of 1868, the nanshin-ron policy came to be advanced with the southern regions as a focus for trade and emigration. During the early Meiji era, Japan derived economic benefits from Japanese emigrants to Southeast Asia, among which there were prostitutes who worked in brothels in British Malaya, Singapore, the Philippines, the Dutch East Indies and French Indochina. Nanshin-ron was advocated as a national policy by a group of Japanese ideologues during the 1880s and the 1890s. Writings of the time often presented areas of Micronesia and Southeast Asia as uninhabited or uncivilised and suitable for Japanese colonisation and cultivation.
As Western colonial powers laid claim to territories ever closer to Japan, Meiji leaders sought to strengthen Japan's international position so that it could attain equal status with the West as a sovereign nation. As a result, Japan began to apply the lessons it learned from European imperialism and itself became a colonial power. In its initial stages Nanshin-ron focused primarily on Southeast Asia, and until the late 1920s, it concentrated on gradual and peaceful Japanese advances into the region to address what the Japanese saw as the twin problems of underdevelopment and Western colonialism.
During the first decade of the 20th century, private Japanese companies became active in trade in Southeast Asia. Communities of emigrant Japanese merchants arose in many areas and sold sundry goods to local customers, and Japanese imports of rubber and hemp increased. Large-scale Japanese investment in rubber planting and iron mining occurred in Malaya. Other resources obtained from Southeast Asia included copra and hemp from plantations in Malaya and in Mindanao in the southern Philippines. The Japanese Foreign Ministry established consulates in Manila, Singapore, and Batavia.
With increasing Japanese industrialization came the realization that Japan was dependent on the supply of many raw materials from overseas locations outside its direct control and was hence vulnerable to that supply's disruption. The Japanese need for the promotion of trade, developing and protecting sea routes, and official encouragement of emigration to ease overpopulation arose simultaneously with the strengthening of the Imperial Japanese Navy, which gave Japan the military strength to protect its overseas interests if diplomacy failed.
Pacific islands
The Japanese government began pursuing a policy of overseas migration in the late 19th century as a result of Japan's limited resources and increasing population. In 1875, Japan declared its control over the Bonin Islands. The formal annexation and incorporation of the Bonin Islands and Taiwan into the Empire of Japan can be viewed as first steps in implementation of the "Southern Expansion Doctrine" in concrete terms.However, World War I had a profound impact on the "Southern Expansion Doctrine" since Japan occupied vast areas in the Pacific that had been controlled by the German Empire: the Caroline Islands, Mariana Islands, Marshall Islands, and Palau. In 1919, the island groups officially became a League of Nations mandate of Japan and came under the administration of the Imperial Japanese Navy. The focus of the "Southern Expansion Doctrine" expanded to include the island groups, whose economic and military development came to be viewed as essential to Japan's security.
Theoretical development
Meiji-period nationalistic researchers and writers pointed to Japan's relations with the Pacific region from the 17th-century red seal ship trading voyages, and Japanese immigration and settlement in Nihonmachi during the period before the Tokugawa shogunate's national seclusion policies. Some researchers attempted to find archeological or anthropological evidence of a racial link between the Japanese of southern Kyūshū and the peoples of the Pacific islands.Nanshin-ron appeared in Japanese political discourse around the mid-1880s. In the late 19th century, the policy focused on China, with an emphasis on securing control of Korea and expanding Japanese interests in Fujian. Russian involvement in Manchuria at the turn of the century led to the policy being eclipsed by hokushin-ron. The resulting Russo-Japanese War produced territorial gains for Japan in South Manchuria. After the war, the expansionist aspects of nanshin-ron became more developed, and the policy was incorporated into the national defense strategy in 1907.
In the 1920s and 1930s, the "Southern Expansion Doctrine" gradually came to be formalized, largely through the efforts of the Imperial Japanese Navy's "South Strike Group," a strategic think tank based at the Taihoku Imperial University in Taiwan. Many professors at the university were either active or former Navy officers, with direct experience in the territories in question. The university published numerous reports promoting the advantages of investment and settlement in the territories under Navy control.
In the Navy, the Fleet Faction opposed the Washington Treaty, unlike the Treaty Faction. The former set up a "Study Committee for Policies towards the South Seas" to explore military and economic expansion strategies and cooperated with the Ministry of Colonial Affairs to emphasize the military role of Taiwan and Micronesia as advanced bases for further southern expansion.
Economic development
In 1920, the Foreign Ministry convened the Nan-yo Boeki Kaigi to promote South Seas commerce. In 1928, it published Boeki, Kigyo oyobi imin yori mitaru Nan'yo. The term Nan-yo kokusaku first appeared.The Japanese government sponsored several companies, including the Nan'yō Takushoku Kabushiki Kaisha, the Nan'yō Kōhatsu Kabushiki Kaisha, and the Nan'yō Kyōkai with a mixture of private and government funds for development of phosphate mining, sugarcane, and coconut industries in islands and to sponsor emigrants. Japanese Societies were established in Rabaul, New Caledonia, Fiji, and New Hebrides in 1932 and in Tonga in 1935.
The success of the Navy in the economic development of Taiwan and the South Seas Mandate through alliances among military officers, bureaucrats, capitalists, and right-wing and left-wing intellectuals contrasted sharply with Army failures in the Chinese mainland.
Increasing militarization
The Washington Naval Treaty had restricted the size of the Japanese Navy and also stipulated that new military bases and fortifications could not be established in overseas territories or colonies. However, in the 1920s, Japan had already begun the secret construction of fortifications in Palau, Tinian and Saipan.To evade monitoring by the Western powers, they were camouflaged as places to dry fishing nets or coconut, rice, or sugar-cane farms, and Nan'yō Kohatsu Kaisha in co-operation with the Japanese Navy, assumed responsibility for construction.
The construction increased after the even more restrictive London Naval Treaty of 1930, and the growing importance of military aviation led Japan to view Micronesia to be of strategic importance as a chain of "unsinkable aircraft carriers" protecting Japan and as a base of operations for operations in south-west Pacific.
The Navy also began examining the strategic importance of Papua and New Guinea to Australia since it was aware that the Australian annexation of those territories had been motivated in large part in an attempt to secure an important defense line.
Adoption as national policy
In 1931, the "Five Ministers Meeting" defined the Japanese objective of extending its influence in the Pacific but excluded areas such as the Philippines, the Dutch East Indies, and Java, which might provoke other countries. Nanshin-ron became official policy after 1935 and was officially adopted as national policy with the promulgation of the Toa shin Chitsujo in 1936 at the "Five Ministers Conference", with the resolution to advance south peacefully.World War II
By the start of World War II, the policy had evolved in scope to include both the Pacific and Southeast Asia. The doctrine also formed part of the basis of the Greater [East Asian Co-Prosperity Sphere], which was proclaimed by Japanese Prime Minister Konoe Fumimaro from July 1940. Resource-rich areas of Southeast Asia were earmarked to provide raw materials for Japan's industry, and the Pacific Ocean was to become a "Japanese lake." In September 1940, Japan occupied northern French Indochina, and in November, the Pacific Islands Bureau was established by the Foreign Ministry.During the war Japan engaged in military invasions, such as the Malayan campaign of December 1941, which were a result of an expansionist policy that had its origins in, among other factors, the country's overseas commercial ventures. Following the Japanese invasion of the Philippines an unsuccessful attempt was made to switch large areas of sugar-producing land to cotton production. After the Japanese attack on Pearl Harbor, Japan went on to capture islands across the Pacific. Failing to achieve a negotiated peace with the US, Japan heavily fortified the islands that were in strategic locations to form a defensive perimeter against US counter-invasion. The Japanese strategy failed to consider island hopping, in which US Marines would skip heavily defended islands and capture easier targets, which left the Japanese troops in the fortifications without supplies and liable to starvation and disease.
The events of the Pacific War from December 1941 overshadowed further development of the "Southern Expansion Doctrine", but the Greater [East Asia Ministry] was created in November 1942, and a Greater East Asia Conference was held in Tokyo in 1943. During the war, the bulk of Japan's diplomatic efforts remained directed at Southeast Asia. The "Southern Expansion Doctrine" was brought to an end by the Japanese surrender at the end of the war.