national interest is self-defeating and may lead to the erosion of power, to America's detriment. Others argue that Kennan, a proponent of the Marshall Plan (which gave out bountiful American aid to post-WW2 countries), might agree that Clinton's aid functioned strategically to secure international leverage: a diplomatic maneuver well within the bounds of political realism as described by Hedley Bull. Realists often hold that statesmen tend towards realism whereas realism is deeply unpopular among the public. When statesmen take actions that divert from realist policies, academic realists often argue that this is due to distortions that stem from domestic politics. However, some research suggests that realist policies are actually popular among the public whereas elites are more beholden to liberal ideas. Abrahamsen suggested that realpolitik for middle powers can include supporting idealism and liberal internationalism. Historical branches and antecedents Historian Jean Bethke Elshtain traces the historiography of realism: The genealogy of realism as international relations, although acknowledging antecedents, gets down to serious business with Machiavelli, moving on to theorists of sovereignty and apologists for the national interest. It is present in its early modern forms with Hobbes's Leviathan (1651). While realism as a formal discipline in international relations did not arrive until World War II, its primary assumptions have been expressed in earlier writings. Modern realism began as a serious field of research in the United States during and after World War II. This evolution was partly fueled by European war migrants like Hans Morgenthau, whose work Politics Among Nations is considered a seminal development in the rise of modern realism. Other influential figures were George F. Kennan (known for his work on containment), Nicholas Spykman (known for his work on geostrategy and containment), Herman Kahn (known for his work on nuclear strategy) and E. H. Carr. Classical realism Classical realism states that it is fundamentally the nature of humans that pushes states and individuals to act in a way that places interests over ideologies. Classical realism is an ideology defined as the view that the "drive for power and the will to dominate [that are] held to be fundamental aspects of human nature". Prominent classical realists: Hans Morgenthau Reinhold Niebuhr – Christian realism Raymond Aron George Kennan Liberal realism or the English school or rationalism The English school holds that the international system, while anarchical in structure, forms a "society of states" where common norms and interests allow for