World War I was a significant event where the United States played a crucial role in turning the tide of the conflict. General John J. Pershing's decision to keep American troops together as a unified force, rather than dispersing them among European armies, was key to ending the war. The U.S. Army mobilized and trained four million men in just nineteen months, shipping two million to France. The efforts of both well-known officers like Pershing, MacArthur, Patton, and Marshall, as well as the unknown soldiers in the trenches, were highlighted in the successful push against the Germans.