Ever since the Chinese Communists came to power in 1949, they have regarded Japan as a major target in their efforts to expand Communist influence in Asia. [...] Japan in the Far East, like Germany in Central Europe, occupies a key position and represents a major obstacle to the spread of communism.
The decline of Chinese influence in Northeast Asia brought little gain to the Koreans, however, for both Russia and Japan competed to replace China as the dominant power. At the end of the Sino-Japanese War of 1894-1895 Japan compelled China to recognize Korea's complete independence. Ten years later, after the Russo-Japanese War, it forced the Russians to acknowledge Japan's "paramount political, military, and economic interests" in Korea, and, with their hands freed by this double victory, the Japanese first established a protectorate over the peninsula and then finally annexed it in 1910.
With the notable exception of Thailand, the entire area was dominated by Western colonialism until World War II. Then Southeast Asia was conquered by Japan, and the Japanese occupation helped to shatter the structure of Western colonial power, giving added impetus to the growing strength of anticolonialism and nationalism. By the end of the war nationalism had become the dominant political force in South and Southeast Asia, and within a very few years after the war most of the nations in the region had achieved their independence, leaving only a few pockets of colonial rule.