On the right you'll a U.S. Government pie chart indicating the expansion of the U.S. Army between April of 1917 and it's total strength at war's end (November, 1918). The chart also illustrates the shrinkage in National Guard units within the same period.
"When the World War One was declared there were 200,000 men in the Army. Two-thirds of these were Regulars and one-third National Guardsmen who had been called to Federal service for the duty along the Mexican border. When the war ended this force had been increased to 20 times its size and 4,000,000 men had served."
Click here to read what the young women of France thought about the Doughboys.
Read about the W.W. I growth of the U.S. Marine Corps...
Click here to read more statistics about the American military of the First World War.