Structural realism

Neorealism or structural realism is a theory of international relations that says power is the most important factor in international relations. It was first outlined by Kenneth Waltz in his 1979 book Theory of International Politics. Alongside neoliberalism, neorealism is one of the most influential contemporary approaches to international relations; the two perspectives have dominated international relations theory for the last decade. Neorealism emerged from the North American discipline of political science, and reformulates the classical realist tradition of E.H. Carr, Hans Morgenthau, and Reinhold Niebuhr.

Neorealism is subdivided into defensive and offensive neorealism.

Neorealism is an ideological departure from Hans Morgenthau's writing on classical realism. Classical realism originally explained the machinations of international politics as being based on human nature, and therefore subject to the ego and emotion of world leaders. Neorealist thinkers instead propose that structural constraints—not strategy, egoism, or motivation—will determine behavior in international relations. Kenneth Waltz made significant distinctions between his position on the three types of international relations in defensive neorealism and that of Morgenthau in his book Man, the State, and War from the late 1950s. John Mearsheimer made significant distinctions between his version of offensive neorealism and Morgenthau in this co-authored book on Israel with Stephen Walt at Harvard University titled The Israel Lobby and U.S. Foreign Policy.

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