Classical realism is an international relations theory from the realist school of thought. Realism makes the following assumptions: states are the main actors in the international relations system, there is no supranational international authority, states act in their own self-interest, and states want power for self-preservation. Classical realism differs from other forms of realism in that it places specific emphasis on human nature and domestic politics as the key factor in explaining state behavior and the causes of inter-state conflict. Classical realist theory adopts a pessimistic view of human nature and argues that humans are not inherently benevolent but instead they are self-interested and act out of fear or aggression. Furthermore, it emphasizes that this human nature is reflected by states in international politics due to international anarchy. Classical realism first arose in its modern form during the interwar period of (1918-1939) as the academic field of international relations began to grow during this era. Classical realism during the inter-war period developed as a response to the prominence of idealist and utopian theories in international relations during the time. Liberal scholars at the time attributed conflict to poor social conditions and political systems whilst, prominent policy makers focused on establishing a respected body of international law and institutions to manage the international system. These ideas were critiqued by realists during the 1930s. After World War II, classical realism became more popular in academic and foreign policy settings. E. H. Carr, George F. Kennan, Hans Morgenthau, Raymond Aron, and Robert Gilpin are central contributors to classical realism. During the 1960s and 70s classical realist theories declined in popularity and became less prominent as structural realist (neorealist) theorists argued against using human nature as a basis of analysis and instead proposed that explaining inter-state conflict through the anarchic structure of the international system was more empirical.
Mark Pauly, Duygu Ceylan, Boris Neubert, Ngoc Minh Dang