How would you define the role of Japan in the American movement of expansionism?

After the conclusion of the war, Japanese leaders gained a free hand in Korea. Korean opposition to Japanese “reforms” was no longer tolerated. Itō Hirobumi, sent to Korea as resident general, forced through treaties that gave Korea little more than protectorate status and ordered the abdication of the Korean king. Itō’s assassination in 1909 led to Korea’s annexation by Japan the following year. Korean liberties and resistance were crushed. By 1912, when the Meiji emperor died, Japan had not only achieved equality with the West but also had become the strongest imperialist power in East Asia. Japan had abundant opportunity to use its new power in the years that followed. During World War I it fought on the Allied side but limited its activities to seizing German possessions in China and the Pacific. When China sought the return of former German holdings in Shantung province, Japan responded with the so-called Twenty-one Demands, issued in 1915, that tried to pressure China into widespread concessions ranging from extended leases in Manchuria and joint control of China’s coal and iron resources to policy matters regarding harbours and the policing of Chinese cities. While giving in on a number of specific issues, the Chinese resisted the most extreme Japanese demands that would have turned China into a Japanese ward. Despite its economic gains, Japan’s World War I China policy left behind a legacy of ill feeling and distrust, both in China and in the West. The rapaciousness of Japanese demands and China’s chagrin at its failure to recover its losses in the Treaty of Versailles (1919) cost Japan any hope of Chinese friendship. Subsequent Japanese sponsorship of corrupt warlord regimes in Manchuria and North China helped to confirm the anti-Japanese nature of modern Chinese nationalism.

The part played by Japan in the Allied intervention in Siberia following the Bolshevik Revolution of 1918 caused further concerns about Japanese expansion. One of the principal reasons for the disarmament conference held in Washington, D.C., in 1921–22, was to reduce Japanese influence. A network of treaties was designed to place restraints on Japanese ambitions while guaranteeing Japanese security. These treaties included a Four-Power Pact, between Japan, Great Britain, the United States, and France, that replaced the Anglo-Japanese Alliance, and a Five-Power Naval Limitation Treaty (with Italy) that set limits for battleships at a ratio of five for Great Britain and the United States to three for Japan. An agreement on the fortification of Pacific island bases was intended to assure Japan of security in its home waters. Finally a Nine-Power Pact would, it was hoped, protect China from further unilateral demands. Japan subsequently agreed to retire from Shantung, and, shortly thereafter, Japanese armies withdrew from Siberia and northern Sakhalin. In 1925 a treaty with the Soviet Union extended recognition to the U.S.S.R. and ended active hostilities.