Introduction to International Relations Theories

Overview of Key Theories

• There are three main theories of international relations: realism, liberalism, and constructivism. This video introduces the broad contours and main points of these theories.

Realism

• Realism focuses on why great powers go to war, based on key assumptions such as anarchy, power maximization, and self-help.

• The assumption of an anarchic international system means there is no central authority; states must rely on themselves for security.

• Realism operates at a systemic level, treating all states as unitary actors with the core interest of maximizing power or security.

• It concludes that the international system is characterized by a balance of power; if one country increases its power, others will respond similarly.

• While realism does not rule out cooperation between states, it posits that such cooperation is temporary and contingent upon national interests.

Liberalism

• Liberalism is broader than realism and includes three main varieties: liberal institutionalism, economic liberalism, and foreign policy formulation.

• Unlike realists, liberal theorists argue that states are not identical; they emphasize that security maximization isn't the only goal in the international system.

• Scholars focus on how domestic politics—such as political institutions and public opinion—affect state behavior in international relations.

• Liberal theorists conclude that cooperation between states is more likely and can be longer-lasting compared to what realists suggest.

Constructivism

• Constructivism also operates at a systemic level but emphasizes how ideas shape state behavior within the international system.

• Concepts like national identities and sovereignty are seen as socially constructed through state interactions rather than inherent characteristics.