By the time the U.S. Army had joined the war in 1917, they were far behind in the study of camouflage, but they did their best to catch up quickly. The American generals assigned the task camouflage to the Signal Corps, which began to cruise the ranks for artists and sculptors because of their natural abilities understand paint and scale (one of the more well-known W.W. I Signal Corps camofleurs was the painter Grant Wood; click here to read about him).