How were U.S. troops primarily used in World War 1?

U.S. troops in World War I were primarily used as fresh reinforcements for the exhausted Allied forces, with the American Expeditionary Forces (AEF) playing a crucial role in key battles such as the Second Battle of the Marne and the Meuse-Argonne Offensive. They contributed to turning the tide of the war by providing manpower and resources, bolstering morale, and helping to secure significant victories. Additionally, U.S. forces were instrumental in establishing a more coordinated Allied strategy and operational approach during the latter stages of the conflict.