Jeffrey J. Matthews provides a clear and concise account of Alanson B. Houghton's diplomatic experience during the 1920s, and consequently, a fresh assessment of US foreign policy during a pivotal decade in world history. Matthews explores why the United States failed to establish a stable world order during the New Era and additionally sheds light on the key historiographical themes of isolationism, new-imperialism, and corporations. American industrialist and politician Alanson B. Houghton, was the world's most influential diplomat during the "New Era" of the 1920s. Houghton, who served as ambassador to both Germany (1922 through 1925) and Great Britain (1925 through 1929), offers a unique window into the formation and implementation of American foreign policy. As the leading ambassador in Europe, he played a key role in the major diplomatic achievements of the era, including the Dawes Plan for reparations, the Locarno security treaties, and the Kellogg-Briand peace pact. While Houghton's significant contributions to these international accords are fully explored, the major theme of this book is his emergence as chief critic of US foreign policy within the Harding and Coolidge administrations.