During the forty-seven years between victories in the Spanish-American War (1898) and World War II (1945), the United States completed a remarkable transformation from regional to global military power, a transformation made painful at times by vigorous debate over whether to limit or expand America's armed forces. Social reformers, pacifists, and fiscal conservatives championed the cause of disarmament; others resisted calls for arms control from home and abroad, insisting that American military "preparedness" was vital. During the 1920s, in the backlash against American involvement in World War I, disarmament advocates enjoyed the diplomatic success of the Washington Naval Treaty system, but the naval arms control regime proved temporary. Ultimately the Great Depression, along with waning international cooperation and growing threats to global security, enervated the American arms control movement.

The Hague Conference, World War I

In 1899, U.S. armament policy was a...