Introduction

During the First World War the US Army grew from a constabulary force of about 100,000 professionals to a conscript army of four million. The Navy changed in an equally rapid fashion, from a force built around a few powerful battleships to one consisting of hundreds of smaller craft for combatting submarines. The American military effort was immense, and in some respects unique – supporting a 2 million man expeditionary force 3,000 miles from home, fighting a war with allies for the first time since 1783, and attempting to mobilize the entire industrial economy to prosecute the war. To a considerable extent traditional practices, in Russell Weigley's terms ‘the American way of war,’ shaped wartime performance at all levels – political, strategic, operational, and tactical. American effectiveness in each of these spheres depended on how readily the military adapted its past experience to the demands of the world war situation. A few key issues, including how to use US combat troops overseas, shipping shortages, and the difficulties of industrial mobilization, had an impact on military effectiveness at all levels. Perhaps the most significant limitation on American effectiveness, especially operationally and tactically, was the short time the United States was an active belligerent. The Americans, despite a massive war effort, had little opportunity, because they had so little time, to learn from their experience and improve effectiveness.