Washington Disarmament Conference

The Washington Naval Conference, also called the Washington Arms Conference or the Washington Disarmament Conference, was a military conference called by U.S. President Warren G. Harding and held in Washington, D.C., from 12 November 1921 to 6 February 1922. Conducted outside the auspice of the League of Nations, it was attended by nine nations—the United States, Japan, China, France, Britain, Italy, Belgium, Netherlands, and Portugal—regarding interests in the Pacific Ocean and East Asia. Soviet Russia was not invited to the conference. It was the first international conference held in the United States and the first arms control conference in history, and as Kaufman, 1990 shows, it is studied by political scientists as a model for a successful disarmament movement.

Held at Memorial Continental Hall in downtown Washington DC, it resulted in three major treaties: Four-Power Treaty, Five-Power Treaty (more commonly known as the Washington Naval Treaty), the Nine-Power Treaty, and a number of smaller agreements. These treaties preserved peace during the 1920s but were not renewed in the increasingly hostile world of the Great Depression.

The world's popular mood was peace and disarmament throughout the 1920s. Women had just won the right to vote in many countries, and they helped convince politicians that money could be saved, votes won, and future wars avoided by stopping the arms race. At the end of the Great War, Britain still had the largest navy afloat but its big ships were becoming obsolete, and the Americans and Japanese were rapidly building expensive new warships. Britain and Japan were allies in a treaty that was due to expire in 1922. Although there were no immediate dangers, observers increasingly pointed to the American-Japanese rivalry for control of the Pacific Ocean as a long-term threat to world peace. By this time, the British realized they had best cast their lot with Washington rather than Tokyo. To stop a needless, expensive and possibly dangerous arms race, the major countries signed a series of naval disarmament agreements.

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