“In April 1917 the United States, with an army of 133,000 men, entered the war in which the belligerents had more that six million men engaged on the Western Front alone. The European national forces were organized into armies each containing three to five corps, each corps usually consisting of two divisions. The American army had no organized military unit higher than a regiment. Although the divisional structure existed on paper, no American soldiers since the Civil War had taken the field as a division, with all the coordination of infantry and artillery, of staff and field, of intelligence and operations, that that requires. All this had to be learned and put into practice. A national army fleshed out to ten times the size of its existing regimental skeleton had to be created, which meant recruited, officered, trained, equipped, shipped overseas, assembled, supplied, coordinated in its arms and branches, and further trained before it could fight. For this task the General Staff had made no arrangements or any general plan of mobilization.” – Barbara Tuchman, Stillwell and the American Experience in China