International relations is the study of how countries interact with each other in a global context. It is a major multidiscipline within political science that combines insights from the disciplines of law, history, sociology, economics, and philosophy. Contemporary issues such as global poverty, economic integration, and security demand interdisciplinary analysis.
International institutions have become an important part of international relations in recent decades. The North Atlantic Treaty Organization (NATO) is a case in point—it provides defense and deterrence, facilitates trade and economic activity, and brings its members together on important diplomatic issues. Other examples include the World Trade Organization and international nongovernmental organizations such as Amnesty International and Human Rights Watch.
The discipline of international relations came into its own after the terrible devastation of World War I in Europe. This war led intellectuals to reconsider the nature of international society and the causes of conflict among states. They also realized that public education should include foreign affairs and that universities should promote research and teaching on such subjects.
The most widely accepted theory of international relations is realism, which argues that the world is anarchic and that conflicts are inevitable unless great powers take decisive action to prevent them. The alternative is liberalism, which focuses on cooperation to achieve national goals without the use of force. It also recognizes that individuals and international organizations, as well as state actors, play a crucial role in shaping the international environment.