Washington Naval Conference The Washington Naval Conference , also called the Washington Arms Conference or the Washington Disarmament Conference , was a military conference called by President Warren G . Harding and held in Washington from 12 November 1921 to 6 February 1922 . Conducted outside the auspices 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 disarmament 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 , 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 are also credited with enabling the rise of the Japanese Empire as a naval power leading up to World War II . Background . 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 obsolescent , 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 it had best cast its 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 . Meeting . The American delegation , led by Secretary of State Charles Evans Hughes , included Elihu Root , Henry Cabot Lodge and Oscar Underwood , the Democratic minority leader in the Senate . The primary objective of the conference was to restrain Japanese naval expansion in the waters of the west Pacific , especially with regard to fortifications on strategically valuable islands . Their secondary objectives were intended to ultimately limit Japanese expansion , but also to alleviate concerns over possible antagonism with the British . They were : first , to eliminate Anglo - American tension by abrogating the Anglo - Japanese alliance ; second , to agree upon a favorable naval ratio vis - à - vis Japan ; and , third , to have the Japanese officially accept a continuation of the Open Door Policy in China . The British , however , took a more cautious and tempered approach . Indeed , British officials brought certain general desires to the conference — to achieve peace and stability in the western Pacific , avoid a naval arms race with the United States , thwart Japanese encroachment into areas under their influence , and preserve the security of Singapore , Hong Kong , and Dominion countries — but they did not enter the conference with a specific laundry list of demands ; rather , they brought with them a vague vision of what the western Pacific should look like after an agreement . Japanese officials were more focused on specifics than the British , and approached the conference with two primary goals : first , to sign a naval treaty with Britain and the United States , and , secondly , to obtain official recognition of Japan ’ s special interests in Manchuria and Mongolia . Japanese officials also brought other issues to the conference — a strong demand that they remain in control of Yap , Siberia , and Tsingtao , as well as more general concerns about the growing presence of American fleets in the Pacific . The American hand was strengthened by the interception and decryption of secret instructions from the Japanese government to its delegation . The message revealed the lowest naval ratio that would be acceptable to Tokyo ; U . S . negotiators used this knowledge to push the Japanese to it . This success , one of the first in the U . S . government ' s budding eavesdropping and cryptology efforts , led eventually to the growth of such agencies . Policies agreed upon . The Washington Conference was called by President Warren Harding and run by Secretary of State Charles Evans Hughes . Harding demanded action in order to gain domestic political credit . Hughes — helped by the cryptographers who were reading the Japanese diplomatic secrets — brilliantly engineered a deal that everyone thought best for themselves . To resolve technical disputes about the quality of warships , the conferees adopted a quantitative standard , based on tonnage displacement ( a simple measure of the size of a ship . ) A ten - year agreement fixed the ratio of battleships at 5 : 5 : 3 — that is 525 , 000 tons for the USA , 525 , 000 tons for Britain , and 315 , 000 tons for Japan . Smaller limits with a ratio of 1 . 7 applied to France and Italy . The dominant weapons systems of the era — battleships — could be no larger than 35 , 000 tons . The major powers allowed themselves 135 , 000 : 135 , 000 : 81 , 000 tons for the newfangled aircraft carriers . The Washington Conference exactly captured the worldwide popular demand for peace and disarmament ; without it , the US , Britain and Japan would have engaged in an expensive buildup , with each worried the other two might be getting too powerful . The agreements forced the US to scrap 15 old battleships and 2 new ones , along with 13 ships under construction . Britain had to scrap ships too — indeed , more warships were lost at Washington than at any battle in history . The naval treaty was concluded on February 6 , 1922 . Ratifications of that treaty were exchanged in Washington on August 17 , 1923 , and it was registered in " League of Nations Treaty Series " on April 16 , 1924 . Japan agreed to revert Shandong to Chinese control by an agreement concluded on February 4 , 1922 . Ratifications of that agreement were exchanged in Beijing on June 2 , 1922 , and it was registered in " League of Nations Treaty Series " on July 7 , 1922 . Results . The Washington Naval Treaty led to an effective end to building new battleship fleets and those few ships that were built were limited in size and armament . Numbers of existing capital ships were scrapped . Some ships under construction were turned into aircraft carrier s instead . Even with the Washington Treaty , the major navies remained suspicious of each other , and for a brief while ( 1927 – 30 ) engaged in a race to build cruisers which had been limited to size ( 10 , 000 tons ) but not numbers . That oversight was resolved on value of cruisers by the London Naval Treaty of 1930 , which specified a 10 : 10 : 7 ratio for cruisers and destroyers . For the first time submarines were also limited , with Japan given parity with the US and Britain at 53 , 000 tons each . ( Submarines typically displaced 1 , 000 - 2 , 000 tons each . ) The U . S . Navy maintained an active building program that replaced obsolescent warships with technically more sophisticated new models in part because its construction yards were important sources of political patronage , and well protected by Congress . During the New Deal , furthermore , relief funds were used to build warships . " The naval program was wholly mine , " President Roosevelt boasted . Termination . The pacts and treaties that resulted from the Washington Naval Treaty remained in effect for fourteen years until Japan ended participation in 1936 .