Liberal internationalism is a school of thought in international relations holding that peace, prosperity, and cooperation among states are best achieved through democratic governance, economic interdependence, international institutions, and a rules-based international order. It contrasts with Realism (International Relations), which emphasizes power and self-interest as the primary drivers of state behavior, and is sometimes used interchangeably with related but distinct terms such as “liberal idealism” or “Wilsonianism,” though scholars differ on the precise boundaries of the term. See liberal-internationalism-definitional-debate for contested framings of the concept itself.

Liberal internationalism developed from classical liberal political theory and gained prominence in the early twentieth century, particularly through the diplomacy of U.S. President Woodrow Wilson and the founding of the League of Nations. For a fuller historical account, see liberal-internationalism-history.

As an analytical framework, liberal internationalism remains one of the principal paradigms taught alongside realism and constructivism in international relations scholarship. As a policy orientation, it has historically informed the foreign policy approaches of various Western governments, particularly the United States and member states of the European Union, including support for institutions such as the United Nations, the World Trade Organization, and NATO. Since the 2010s, the framework has faced renewed scrutiny amid the rise of populist and nationalist political movements, debates over the costs and benefits of globalization, and shifts in the international distribution of power, including the growing influence of China and other non-Western states. Scholars and policymakers disagree on whether the post-1945 “liberal international order” is in decline, undergoing transformation, or remains resilient; this disagreement is treated in greater depth in liberal-internationalism-decline-debate.

The term's relationship to American political ideology is also contested: some commentators associate liberal internationalism closely with the foreign policy traditions of the U.S. Democratic Party, while others note that historically both major American parties have included internationalist and non-internationalist factions. See Modern American Progressivism (a viewpoint page of a related topic) for one perspective on this association.

• liberal-internationalism-institutionalist-viewpoint - Emphasizes that international institutions, treaties, and organizations reduce conflict and facilitate cooperation by lowering transaction costs and increasing transparency among states.
• liberal-internationalism-democratic-peace-viewpoint - Holds that the spread of democratic governance is a primary mechanism for reducing interstate conflict, drawing on democratic peace theory.
• liberal-internationalism-economic-interdependence-viewpoint - Emphasizes free trade and economic integration as the primary mechanism for fostering peaceful relations among states.
• liberal-internationalism-realist-viewpoint - Rejects core liberal internationalist assumptions, arguing that international institutions are constrained by state power and self-interest and cannot reliably override it.
• liberal-internationalism-restraint-viewpoint - A skeptical or “restrainer” view, often associated with realist or progressive critics, arguing that liberal internationalist policy in practice has justified costly military interventions and overextension.
• liberal-internationalism-nationalist-viewpoint - A nationalist or sovereigntist critique holding that liberal internationalist institutions and commitments undermine national sovereignty and democratic accountability.

• liberal-internationalism-iraq-war-controversy - Dispute over whether the 2003 invasion of Iraq, justified partly in terms of democracy promotion, represented an application or a betrayal of liberal internationalist principles.
• liberal-internationalism-humanitarian-intervention-controversy - Ongoing dispute over the legitimacy and consequences of interventions justified on liberal internationalist grounds, such as in Libya in 2011.

• liberal-internationalism-history
• liberal-internationalism-decline-debate
• liberal-internationalism-definitional-debate
• liberal-internationalism-institutionalist-viewpoint
• liberal-internationalism-democratic-peace-viewpoint
• liberal-internationalism-economic-interdependence-viewpoint
• liberal-internationalism-restraint-viewpoint
• liberal-internationalism-nationalist-viewpoint
• Realism (International Relations)
• liberal-internationalism-realist-viewpoint
• liberal-internationalism-iraq-war-controversy
• liberal-internationalism-humanitarian-intervention-controversy
• Modern American Progressivism

1. G. John Ikenberry, *Liberal Leviathan: The Origins, Crisis, and Transformation of the American World Order* (Princeton: Princeton University Press, 2011).
2. Tony Smith, *America's Mission: The United States and the Worldwide Struggle for Democracy in the Twentieth Century*, expanded ed. (Princeton: Princeton University Press, 2012).
3. Michael W. Doyle, “Liberalism and World Politics,” *American Political Science Review* 80, no. 4 (1986): 1151-1169.
4. John J. Mearsheimer, *The Great Delusion: Liberal Dreams and International Realities* (New Haven: Yale University Press, 2018).
5. Stephen M. Walt, *The Hell of Good Intentions: America's Foreign Policy Elite and the Decline of U.S. Primacy* (New York: Farrar, Straus and Giroux, 2018).