“Politics Among Nations: The Struggle for Power and Peace” by Hans J. Morgenthau, first published in 1948 and widely regarded as a classic in international relations theory, presents the foundations of classical realism. Morgenthau argues that international politics is governed by objective laws rooted in human nature, which drives states to seek power and act in their own national interest. In an anarchic international system with no central authority, the primary concern of each state is survival, leading to a perpetual struggle for power.

Morgenthau outlines six principles of political realism, emphasizing that political actions should be based on rational calculations of interest, rather than moral or ethical considerations. He critiques idealistic views, such as those that emphasize global cooperation or moral diplomacy, and argues that peace can only be achieved through a balance of power, where no single state dominates. The book, especially in its sixth edition, remains influential for its insights into the nature of power politics, diplomacy, and the challenges of maintaining international peace.