United States diplomatic policy towards European Jews, Zionists and Israelis remains vitally important to the stability and international posture of numerous countries. This study traces the evolution of that policy from its roots in isolated responses to post-World War I anti-semitism to its coherent statement in the post-World War II era. Topics such as the Jewish minority problem in Europe, the history of US-Zionist relations, and the American response to the Holocaust, often treated separately, are here studied together, and their integral part within US policy emphasized. Told in narrative form, this is the story of the origins of US policy toward European Jews and the Jews' reaction to that policy. "Reluctant Ally" is an account of how the American outrage at mistreatment of European Jewry joined with the Zionist movement to support the inevitable settling of Palestine. Policy changed rapidly from 1900 to mid-century, and this discussion of the various aspects of that development brings many new facts to light and furnishes information that can enhance understanding of current US policy toward Israel as well as the current war in the Middle East.