Japanese Expansion in East Asia (1931-1941)

In 1854, the United States and Japan signed the Treaty of Kanagawa, which opened Japan to foreign influence. Thereafter, during the Meiji period, the Japanese began to modernize; industrialization required access to resources that Japan is not rich in including iron, coal, and oil. Partly in search of these resources, Japan began to expand its power, taking over Korea and leasing the Liaodong Peninsula (through which a railroad ran into Manchuria) from China. In the treaties that ended World War I, Japan was allotted some German territories in the Pacific; furthermore, its economy had prospered during the war.

Concerned about Japan’s expanding power, during the 1920s the US, Japan, and European powers signed several economic and military treaties, which were referred to as the Washington Treaty System. However, the Great Depression impacted Japan by causing a drastic decrease in trade and a consequent increase in unemployment. Extreme hardship in the countryside led to anger against the government and big businesses. By the late 1920s, there was rising concern in Japan about the security of Japanese interests in Manchuria. Clashes between Chinese and Japanese troops added to the tension, and, as the Japanese press consistently depicted the Chinese as at fault, in Japan the public began to support a nationalist and militarist agenda.

In 1931, at Mukden in the Liaodong Peninsula, a Japanese army unit called the Kwantung Army blew up a section of railroad; they blamed the Chinese for the Mukden Incident and used this as the pretext for an invasion of Manchuria. This was condemned by the League of Nations, which demanded Japanese withdrawal from Manchuria and launched an investigation. The investigation produced the Lytton Report, which condemned Japanese imperialism. Nevertheless, the Japanese set up a puppet state called Manchukuo, ruled by the deposed Chinese Emperor, Puyi.

The United States, too, condemned Japanese expansion, but stopped at issuing a statement of non-recognition (the Stimson Doctrine). This did nothing to stop Japanese expansion but allowed US trade with Asia to continue, which the US considered to be a priority. Furthermore, the Japanese bombed Shanghai in 1932. In China, at the time, a civil war was taking place between the Nationalist Guomindang (GMD) and the Communists. The result was that in 1933, the GMD signed a treaty ceding Manchuria to Japan so that the GMD could focus on battling the Communists.

In 1933 also, Japan withdrew from the League of Nations. In Japan, the seizure of Manchuria led to celebration, but a struggle ensued between different army factions. Eventually, in 1937, Hideki Tojo became the leader of the Kwantung Army. In early July, 1937, Japanese forces, on a training exercise, clashed with Chinese forces at the Marco Polo Bridge. The Marco Polo Bridge Incident became the pretext for the Japanese invasion of China and the beginning of the Second Sino-Japanese War (1937-1945). The invasion led to the formation of the Second United Front in China (between the Communists and the Guomindang).

The Japanese pressed southward, taking Beijing in August, Shanghai in November, and then Nanjing in December. Following the surrender of Nanjing, atrocities were committed against civilians, including tens of thousands of rapes and murders; this is called the Rape of Nanjing. The Chinese retreated but continued to resist, although hampered by lack of weapons and equipment.

The United States and Britain discussed attempting to act as mediators in the Second Sino-Japanese War (1937-1945), but the US ultimately rejected this move. Due to the isolationist attitudes that were prevalent in the United States at this time, as well as the Neutrality Acts, the US was determined not to become involved in the conflict spreading through Asia. Tension rose, however, when the US gunboat the USS Panay was sunk in 1937 by Japanese aircraft as it was being used to help evacuate US citizens from Nanjing.

The Japanese claimed not to have seen the US flags painted on the Panay’s deck, and apologized for the incident. Furthermore, the US continued to trade with Japan, supplying it with metal as well as with over 80% of Japanese oil imports. However, as the Sino-Japanese War continued, the US began to push back against Japanese expansionism. Many US citizens were outraged by the Japanese attacks on Chinese civilians, and the US responded with a “moral embargo” discouraging US businesses from selling aircraft to Japan which Japan might then use to expand its attacks on China.

The US also began supporting the Guomindang (GMD) with aid both in the form of money and in the form of aircraft. In 1939, the US ended a 1911 trade agreement with Japan. This made it possible for the US to place embargoes on many different products. By the winter of 1940, there were embargoes on weapons, ammunition, many types of metal including iron and steel, machine tools, and other commodities. Deeply embroiled in its war with China and lacking resources it needed to continue fighting, the Japanese army found itself overextended and in a war that it could not easily end.

Meanwhile, in Japan, anti-democratic moves were taking place. To create the unity necessary to meet the demands of the war, political parties were eliminated and replaced by the Imperial Rule Assistance Association (IRAA) in 1940. The IRAA wielded vast economic  and social power and formed the focus of the nationalist and militarist cultural transformation of Japan. In September 1940, with war already raging in Europe, Japan, Germany, and Italy signed the Tripartite Pact. The Japanese would benefit from this because they could gain control over European territories in Asia.

Japan expressed its vision for Asia (and for Japanese dominance) in the creation of the New Order of East Asia (1938) and the Greater East Asia Co-Prosperity Sphere, unveiled in August 1940, in which Japan declared its intention to spread its culture throughout Asia and drive out Western powers. Japan’s leaders identified the creation of this Co-Prosperity Sphere with Japan’s national defense. The announcement of the creation of the Greater East Asia Co-Prosperity Sphere alarmed the US, as it would interfere with the “open door” policy which allowed profitable free trade with Asia to continue.

Furthermore, in July 1941, Japanese forces took southern French Indochina. This threatened the Philippines (US territory), the Dutch East Indies, and Singapore (British). The US, Britain, and the Dutch East Indies then froze Japanese assets and, in August, the US placed an embargo on exports of oil to Japan. This meant loss of a resource that was essential if Japan hoped to continue its expansion in Asia. Negotiators failed to reach a trade agreement, and in October, 1941, Hideki Tojo became prime minister. The decision to go to war against Britain and the United States was made on December 1st, and on December 7th, 1941, the Japanese bombed Pearl Harbor, leading to the US entry into World War II.