During World War I, hundreds of Americans traveled to Italy as volunteers for the American Red Cross (ARC). Through their relief activities for Italian civilians, these individuals served both diplomatic and social-reform agendas. They packaged medical and social aid with a clear message of American alliance, presenting the ARC as a vanguard of the U.S. military that was prepared to assist Italy's war effort in the absence of American troops. Emphasizing American methods, expertise, and alliance, ARC representatives also enacted reforms with the ambition to mold Italy into their vision of a modern western nation. This article argues that international humanitarian aid buttressed U.S. international involvement, both political and cultural, during the Wilsonian era. Further, by examining the connections between social politics and foreign relations in Italy, it demonstrates that the boundaries of the transatlantic progressive community extended beyond the North Atlantic.