Reports of the United States’ rise to a lead role on the global stage in the early twentieth century have been greatly exaggerated. As many Americans at the time recognized, the United States continued to have less capacity for overseas power projection and remained far more dependent on the world’s reigning hegemon, Great Britain, than is generally now realized. The United States, it is true, acquired an overseas empire in 1898. But it lacked basic attributes of economic sovereignty, naval power, and domestic consensus on the desirability of global great-power status. Even after World War I, a better candidate than the Spanish-American War as the moment when the United States became a leading global power, both the material and the cultural basis of that power remained fragile.