International Relations: States and Global Order

Why do nations go to war? Can international cooperation overcome the struggle for power? Do institutions like the United Nations and the European Union make a difference, or are they mere facades for great-power interests? International relations (IR) is the field of political theory that grapples with these questions. It examines how states interact in an international system that lacks a central authority — an “anarchic” system in the technical sense of having no world government. In this system, the same questions that haunt domestic politics — security, justice, order, legitimacy — take on different forms and raise different possibilities.

The Problem of Anarchy

The starting point for most IR theory is the observation that the international system is anarchic. There is no global government to enforce agreements, punish aggression, or maintain order.

Realism

Realism is the oldest and most influential tradition in IR. Realists argue that the anarchic international system forces states to prioritize survival above all else. Because no state can trust others to keep their agreements, each must rely on its own power — military, economic, diplomatic — to ensure its security. This creates a “security dilemma”: one state’s efforts to make itself more secure (building up its army) make other states less secure, prompting them to arm in response, leading to arms races and war.

Classical realists like Hans Morgenthau traced the struggle for power to human nature — an innate lust for dominance. Structural realists (neorealists) like Kenneth Waltz located the cause in the structure of the international system itself. Waltz’s Theory of International Politics (1979) argues that the anarchic structure of the system compels states to behave in certain ways regardless of their internal characteristics. Whether a state is democratic or authoritarian, capitalist or socialist, it must pursue power to survive.

Realism offers powerful explanations for many features of international politics: the persistence of war, the difficulty of cooperation, the importance of military power, and the tendency of states to balance against rising powers. But critics argue that realism is too pessimistic — it cannot explain the long peace among democratic states, the spread of international institutions, or the role of norms and ideas in shaping state behavior.

Liberalism

Liberal IR theory offers a more optimistic vision. Liberals argue that cooperation is possible even in anarchy, thanks to three factors: democracy, economic interdependence, and international institutions.

The democratic peace theory — the strongest empirical finding in IR — holds that democracies rarely if ever fight each other. This is not because democracies are inherently peaceful (they fight non-democracies as often as anyone else) but because democratic norms of peaceful conflict resolution and shared political values make war among democracies unthinkable.

Economic interdependence — trade, investment, global supply chains — raises the cost of war and gives states powerful incentives to resolve disputes peacefully. States that trade with each other are less likely to fight each other.

International institutions — the UN, the World Trade Organization, the International Monetary Fund — facilitate cooperation by providing information, reducing transaction costs, and creating mechanisms for monitoring and enforcement. Robert Keohane’s After Hegemony (1984) showed that institutions can sustain cooperation even after the hegemonic power that created them declines.

To understand the relationship between domestic and international political legitimacy, see Sovereignty and Legitimacy: Foundations of Authority.

Constructivism

Constructivism emerged in the 1990s as a challenge to both realism and liberalism. Constructivists argue that the international system is not a fixed, objective reality but a social construction — shaped by ideas, norms, identities, and culture.

Alexander Wendt’s famous slogan captures this: “Anarchy is what states make of it.” The anarchic international system does not automatically produce self-help and conflict. It does so only because states have constructed an identity as rivals. If states understand themselves as friends (as the United States and Canada do), anarchy produces peaceful coexistence. If they understand themselves as enemies (as the United States and the Soviet Union did), anarchy produces conflict.

Constructivism helps explain phenomena that realism and liberalism struggle with: the abolition of slavery, the delegitimization of colonialism, the spread of human rights norms, and the transformation of European politics from centuries of war to the peaceful integration of the European Union. These changes were driven not by shifts in material power but by changes in ideas and identities.

Key Issues in International Relations

War and Peace

War is the central concern of IR. What causes war, and what conditions make peace possible?

Realists emphasize power transitions — wars often occur when a rising power challenges the dominant position of an established power. The Peloponnesian War, the Thirty Years’ War, and the two World Wars can all be understood through this lens. The rise of China and its challenge to American dominance is the most consequential power transition of the twenty-first century.

Liberals emphasize misperception, nationalist ideology, and the failure of institutions as causes of war. They argue that war is not inevitable but can be prevented through diplomacy, economic integration, and international law.

Constructivists examine how the very concept of war is socially constructed. War is not simply the continuation of politics by other means; it is a social institution governed by norms — about who can fight, how they can fight, and when war is legitimate. The norm against aggressive war (the “jus ad bellum” tradition) has evolved significantly, from the acceptance of war as a sovereign right to the prohibition under the UN Charter.

International Order

How is international order possible without a world government? Theorists identify several sources of order: the balance of power (states balancing against the strongest power), hegemonic stability (a single dominant power providing public goods like security and open trade), and international institutions (creating rules and norms that stabilize expectations).

The post-1945 liberal international order — built by the United States and its allies after World War II — combined all three: American hegemony, international institutions (the UN, NATO, the World Bank), and liberal norms (democracy, human rights, free trade). This order faces significant challenges in the twenty-first century: the rise of China, Russian revisionism, American retrenchment, and populist nationalism within liberal democracies themselves.

Globalization and Its Discontents

Globalization — the increasing integration of economies, societies, and cultures across borders — has transformed international relations. It has lifted hundreds of millions out of poverty, spread technology and ideas, and created a global middle class. But it has also produced inequality, cultural disruption, and a backlash from those left behind.

IR theorists debate whether globalization is making state sovereignty obsolete or whether states are adapting to new challenges. Hyper-globalists argue that global markets and transnational actors have eroded state control. Skeptics counter that states remain powerful and that globalization is a political choice that can be reversed — as the Brexit vote and trade wars of the 2010s demonstrated.

For more on how national identity shapes international conflict and cooperation, see Nationalism: Identity, Belonging, and Conflict.

The Future of International Relations

Contemporary IR theory grapples with new challenges that do not fit neatly into existing frameworks.

Climate Change

Climate change is a collective action problem par excellence. No single state can solve it, and all have incentives to free-ride on others’ efforts. International cooperation on climate change — the Kyoto Protocol, the Paris Agreement — has had limited success. IR theorists examine whether the international system is capable of addressing this existential threat or whether more fundamental changes in political organization are needed.

The Rise of Non-State Actors

IR has traditionally focused on states as the primary actors in international politics. But non-state actors — terrorist groups, multinational corporations, NGOs, transnational social movements — play increasingly important roles. Al Qaeda and ISIS have fought wars with states. Google and Amazon have power rivaling that of many governments. IR theory must account for the diversification of actors in global politics.

Technology and Cyber Conflict

The digital revolution has created new domains of conflict — cyber warfare, information operations, election interference — that challenge traditional IR concepts of sovereignty, territory, and war. What does it mean to be “at war” when the battlefield is computer networks and the weapons are codes and algorithms?

FAQ

What is the difference between realism and liberalism in IR?

Realism emphasizes the struggle for power in an anarchic system, arguing that states prioritize survival and security above all else. Liberalism emphasizes the potential for cooperation through democracy, economic interdependence, and international institutions.

Why don’t democracies fight each other?

The democratic peace theory offers several explanations: shared norms of peaceful conflict resolution, the constraining effect of public opinion and elections, and the transparency of democratic decision-making. However, democracies fight non-democracies as often as anyone else.

Is the European Union a model for global governance?

Some theorists see the EU as a model for how states can transcend the security dilemma through institutional integration, shared sovereignty, and mutual interdependence. Others argue that the EU’s success reflects unique European conditions — post-war exhaustion, American security guarantees, and cultural homogeneity — that cannot be replicated globally.

What is the security dilemma?

The security dilemma arises when one state’s efforts to increase its security (building up its military) reduce the security of other states, prompting them to retaliate, leading to arms races and increased tension between them. It is a tragic dynamic: even states that seek only security can end up in conflict.

Can international law constrain state behavior?

Yes, but imperfectly. International law has no central enforcement mechanism, but it creates expectations, shapes discourse, and imposes costs on violators (reputational damage, sanctions, loss of legitimacy). Most states comply with most international law most of the time, but powerful states can violate it with relative impunity.

What is the liberal international order?

The liberal international order is the system of institutions, norms, and rules established after World War II — including the UN, NATO, the World Bank, the IMF, and the WTO — along with the principles of democracy, human rights, and free trade. It has been associated with unprecedented peace and prosperity but faces challenges from rising powers and internal populist backlash.