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National Defense Acts

National Defense Acts (1916, 1920).These statutes provided major restructuring of the U.S. Army. The 1916 act resulted from the “Preparedness” movement to ready the United States for modern war. It authorized nearly doubling the regular army, to 175,000 (and 286,000 in war), but failed to eliminate state militias as nationalists and regulars desired. Instead, Congress designated the National Guard the primary trained reserve, increased its funding and regulation, and authorized its expansion to 450,000. The law required Guard members to take a dual oath to the nation and their state, enabling the president to “federalize” them and even send them overseas. To prepare reserve army and National Guard officers, Congress established a campus‐based Reserve Officers Training Corps (ROTC) and provided federal funds for summertime officers' training camps for business and professional men. It also authorized steps toward industrial mobilization that led to a Council of National Defense. When the United States entered World War I in 1917, the regular army expanded, the president federalized the National Guard, and Congress authorized temporary wartime selective conscription.

The National Defense Act of 1920 expanded the 1916 legislation and provided for postwar reorganization of the army. The 1920 law governed organization and regulation for three decades—until the Army Reorganization Act (1950)—codifying the three‐component army: regular, National Guard, and Army Reserve. Rejecting peacetime conscription, the lawmakers relied on voluntarism; denying the General Staff's proposal for a 500,000‐man standing army, Congress authorized a regular army of 280,000, a National Guard of 430,000, a skeletal Army Reserve, to be filled with veterans, and expanded programs for commissioning reserve officers. The legislators made permanent some wartime organizational additions: the Financial Department, the Chemical Warfare Service, and the Air Service, which was separated from the Signal Corps. It also rescinded some changes: the Tank Corps was put back in the infantry. Furthering the Elihu Root reforms, the legislation enlarged the General Staff, giving it responsibility for overall military planning. It also authorized an assistant secretary of war for planning business and industrial mobilization. The General Staff's importance in planning and combined operations would become evident in World War II.
[See also Army, U.S.: 1900–41; World War I: Military and Diplomatic Course.]


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John Whiteclay Chambers II

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