Answer:
The United States participated in the Washington Naval Conference of 1921-1922 in order to help reduce tensions and prevent an arms race between the major naval powers of the time, which included the United States, Britain, Japan, and several other countries. The conference resulted in the signing of a number of treaties, including the Five-Power Treaty and the Four-Power Treaty, which established limits on the size and strength of the participating countries' navies. The United States also participated in the conference in order to protect its interests in the Pacific region and to promote international cooperation and stability.