Introduction to the War with Japan
Background. After World War I, Japan's industrial and military power increased, but the modernization of Japanese society caused political conflict. Labor unions, leftists, and liberal political parties called for reforms in government and the economic system. Conservatives feared that such dissent was dangerous to the nation. Ultranationalists and the military scorned Japan's limited democracy, which had been created by the constitution of 1889, and demanded that people give total obedience to the Japanese emperor. Political tensions were made worse by a faltering economy, which neared collapse after the Great Depression began in 1929.
By the early 1930's, Japanese politics and government had become dominated by aggressive militarists who crushed all political opposition. They believed that Japan's future as a military, economic, and political power required territorial expansion in the countries of the western Pacific, especially China. They hoped to establish an empire that would supply the natural resources Japan needed For further industrial development. They also hoped to challenge the dominance of the Western colonial powers in the Far East.
Military Expansion
In September, 1931, Japanese army officers contrived the "Mukden Incident" (a bomb explosion falsely blamed on the Chinese), giving them an excuse to attack and conquer Manchuria, which was then set up as a puppet state called Manchukuo. In January, 1932, the Japanese bombed and occupied Shanghai. These acts aroused indignation throughout the world; in response to protests at the League of Nations, Japan withdrew from the league.
A minor dash between Chinese and Japanese patrols near Peiping (Beijing) on July 7, 1937, was used as an excuse by the Japanese to launch a general war against China. The United States and other nations protested Japan's aggression and refused to recognize the legitimacy of its conquests. War between the United States and Japan was narrowly averted in late 1937 after Japanese airplanes sank the American gunboat Panay in Chinese waters; Japan apologized and paid damages. By 1940, Japan held virtually all of eastern China and had set up a puppet government there. The Chinese, led by Generalissimo (Commander in Chief) Chiang Kai-shek, continued to resist.
Because the Allied powers were fighting a desperate struggle against Germany and Italy, they could not defend their holdings in Asia, and Japan took advantage of this to increase its strength in the Pacific. On July 18, 1940, under pressure from Japan, Britain closed the Burma Road, over which traveled almost all of the supplies the Chinese armies needed to fight Japan. Japan demanded the use of airfields in French Indochina in June, and began to occupy the northern half of that colony in September. In response, the United States halted exports of scrap iron and steel to Japan, and Britain reopened the Burma Road. On September 27, 1941, Japan signed the Berlin Pact, becoming one of the Axis powers.
Japan demanded, and the Vichy French government granted, full military control of French Indochina in July, 1941. The United States, joined by Great Britain and the Netherlands, froze Japanese assets and imposed a near-total trade embargo against Japan.
Diplomatic Negotiations. In October, 1941, General Tojo Hideki became premier of Japan. Soon after, Japan demanded international recognition of its conquests in China and the right to buy oil in the Netherlands East Indies (now Indonesia). Saburu Kurusu was sent to the United States in November as a special envoy to conduct negotiations between Japan and the American government. At the same time, convinced that negotiations would achieve nothing, Japan was secretly preparing for war against the United States.
The United States pressed for an end to Japanese aggression in China and Japan's withdrawal from French Indochina. Japan, however, issued a declaration of war, which was not delivered until after the surprise attack on the American fleet at Pearl Harbor, Hawaii, on December 7, 1941.
Plans
American military planners realized that despite its military buildup, the United States was weak and overextended in the Pacific. In the event of war, the Philippines were expected to be lost, and the American fleet was to fall back to the Netherlands East Indies. After the United States entered the war, the general strategy adopted by the British, Dutch, and Americans was to fight a holding war against Japan and make their main effort against Germany. After Germany surrendered, the full strength of the Allies would be turned against Japan. The second part of the plan was never fully applied, because by the time Germany was defeated, Japan was also near collapse. In the meantime, the United States planned to concentrate its efforts in the Pacific on seizing island bases from which to attack and blockade the Japanese mainland.
Japan intended to extend its empire, which it called the Greater East Asia Co-Prosperity Sphere, over most of the Pacific, and made haste to seize islands to use as bases to protect its conquests. The Japanese expected to fight a limited war. Once they had won the territory they wanted, they intended to defend it until the Allies were worn out and willing to negotiate for peace.
Japan had a large, well-trained, experienced army of 120 divisions. Its troops were courageous, highly skilled in tactical operations, and ably led. The Japanese navy, immediately after Pearl Harbor, was much stronger than the United States Pacific Fleet. The quality of Japanese weapons was good.
Japan was not prepared to fight a prolonged war. It had accumulated stocks of vital raw materials, but once the war began, replenishing them became difficult. Japan's manufacturing output could not be increased greatly. The supply system was poorly organized, and supply problems sometimes became acute. Japan's occupation of eastern China became a great drain upon Japanese resources. Other serious shortcomings were lack of an adequate program to train pilots and lack of modern anti-submarine equipment. Japanese military effectiveness was also hindered by extreme rivalry between the army and the navy, which led to inefficiency in the planning and execution of operations.Important dates in the Pacific: 1941-1942.