The Washington Conference was held on November 12, 1921, and ended on February 6, 1922, with the goal of establishing a Washington System aimed at suppressing Japan. The spoils of war that Japan won in the First World War were not only the well-known Shandong, but also Germany's past colonies in the Nanyang Islands, including today's Northern Mariana Islands, Palau, Marshall Islands and Micronesia West Asian Federation. On the grounds of establishing a new Pacific order, the United States requires the United Kingdom, France and Italy to jointly sign the Four-Power Treaty. On the surface, it requires the five countries of the United States, Britain, Japan, France and Italy to respect each other's sovereignty in the Asia-Pacific region. The above is to deprive the legitimacy of the renewal of the "Anglo-Japanese Alliance" and prevent Japan from seeking the assistance.
United Kingdom against the United States in the future. In fact, the United States' worries about this are completely unnecessary, because the United Kingdom also began to regard Japan as a potential threat, and the "Anglo-Japanese Alliance" was destined to not last after 1923. The Washington Naval Treaty was then signed to limit the development of the Imperial Japanese Navy, strictly stipulating a 5:5:3 ratio of naval development between the United States, the number list United Kingdom, and Japan. Japan has protested against both the United States and the United States, arguing that the proportion of ships built by the United Kingdom and the United States far exceeds that of Japan, which will put Japan in a disadvantageous position in a long-term conflict with the United Kingdom and the United States. However, considering that the British and American navies are scattered in major seas around the world, while the Imperial Japanese Navy is more concentrated in the Asia-Pacific region, such an arrangement is barely acceptable to Japan. The last is the Nine-Power Pact.
Which involves China but is the most political. As the grand strategist Carl von Clausewitz said, war is just an extension of politics through another means. The focus of the Washington Conference in the United States is still on China, to strive for and ensure that Chinese nationalism will survive in the next world war. China and the United States of America advance and retreat together. Therefore, the unsolved case in Shandong must be under the leadership of the United States, with Japan returning Shandong's sovereignty to China as a happy ending. After the United States, Belgium, the United Kingdom, China, France, Italy, Japan, the Netherlands and Portugal completed the signing of the "Nine-Power Pact" on February 6, Japan almost unconditionally returned Shandong to China. With the establishment of the Washington system, the United States gradually replaced the United Kingdom as the big brother of the Western world in the Asia-Pacific region, and the Republic of China must support Japan and the Soviet Union's potential partners. This set of strategic plans is completely in line with the national interests of the Republic of China in the 1920s. Why did Sun Yat-sen hold an opposing attitude.