Hans J. Morgenthau is generally considered to have been a political realist and the transmitter of continental Realpolitik into American letters. But he has also been claimed as an idealist, as a constructivist, and as an ethicist. Some of these claims make sense if we understand that Morgenthau was trained as a lawyer in the German historical tradition. Others can be made sense of if we understand that—self-consciously a “European”—he was continuously adapting his ideas to an American audience and, in the process, being socialized into an American experience. The essays in this roundtable illustrate the “Americanization” of Morgenthau.