Before 1898, there was almost no serious planning in the United States for a major war. By the time of the Pearl Harbor attack in December 1941, by contrast, the United States was able to draw on a quarter-century of formal planning for mobilization. This rise in readiness helped the United States and its allies win World War II. But it also involved serious struggles over American political and cultural ideals.

Preparedness and Anti–Preparedness Movements

One of the most important military preparedness campaigns in American history began just before World War I. This campaign was led by former president Theodore Roosevelt and his friend Leonard Wood, who had been military governor of Cuba after the Spanish-American War. In 1913, when he was serving as the army's chief of staff, General Wood started a summer military training program for college students. This program served as the foundation for the Plattsburg movement...