Negotiated at the Washington Naval Conference, the treaty fixed ratios of capital-ship tonnage among the five powers and halted construction of new battleships for a decade. It represented the first major disarmament agreement of the 20th century, though its restrictions would ultimately unravel in the 1930s as Japan and other signatories pursued rearmament.
After World War I, the great powers faced ruinous naval budgets as the US, Britain, and Japan all planned massive new battleship fleets. American Secretary of State Charles Evans Hughes stunned delegates on the conference's opening day in November 1921 by proposing the immediate scrapping of dozens of existing and planned warships — a proposal so bold that observers said he 'sank more ships in thirty-five minutes than all the admirals of the world had sunk in centuries.'
The resulting treaty, signed February 6, 1922, established a ratio of capital ship tonnage — roughly 5:5:3 for the US, Britain, and Japan respectively — and imposed a building holiday. It was hailed as a triumph of diplomacy over militarism.
Yet the treaty's limits on cruisers and other vessels were looser, spurring competition in other ship classes, and Japan's resentment over its inferior ratio fed a nationalist backlash. Japan formally renounced the treaty's restrictions in 1934, and by the mid-1930s the naval arms race the treaty sought to prevent was resuming in earnest.
Key people: Charles Evans Hughes