Theories of international relations provide a framework for analyzing situations involving interactions between different international actors or the corresponding phenomenon emerging from the decisions and actions of these actors. There are three major theories in international relations, each with its unique core assumptions. These are realism, liberalism, and constructivism.
Note that the aforementioned theories also correspond to schools of thought in international relations theory because each of them has its own particular group of adherents who have further introduced, developed, and used derivative theories.
Three major theories of international relations
1. Realism: The theory of realism in international relations generally assumes that the international system is inherently disorderly and relations are anarchic because primary actors are perpetually locked against a struggle for power and security.
Another general assumption of this theory is that states are the primary actors in the international politics. The reason why international relations are anarchic is that there is no supranational authority that would govern the conduct of these states by enforcing rules.
States desire power to ensure self-preservation nonetheless. The behaviors and actions of these states are directed toward the promotion of their self-interest. There can be no middle ground or moderation with regard to the scope of power accumulation. A state either has power or none at all.
2. Liberalism: The theory of liberalism in international relations directly contradicts the theory of liberalism. Note that realism is about the individuality of states while liberalism is about the necessity of interdependence and cooperation.
General assumptions of liberalism center on the notion that the rejection of power politics is the only possible outcome of international relations. Thus, instead of perceiving the international system as inherently anarchic, liberalism assumes that there are plenty of opportunities for cooperation.
States are not the only primary actors in the international politics according to liberalism. International organizations such as supranational authorities and non-government organizations to include business organizations and non-profit organizations play critical roles in shaping international relations.
3. Constructivism: The theory of constructivism is a delineation from both realism and liberalism. It does not merely perceive international relations as the sole product of the behaviors and actors of primary actors. Instead, this theory underscores the notion that international relations is a social construction.
One specific assumption of constructivism considers international politics as a real of interaction influenced by the identities and practices of actors and directed further by the incessantly changing norms. The motivation behind the behaviors and actions of a state is shaped by their interactions with other states and actors.
Both realism and liberalism consider states or other actors as inherently egoists whose identities and interests have already been in place prior to interaction with other states or actors. However, constructionism perceives these actors as social beings whose identities and interests are the product of social structures.
Other theories of international relations
1. Marxism: Marxism is also a theory in international relations based on the same economic theory that emerged from the works of Karl Marx. The more specific Marxist international relations theories reject realism and liberalism by arguing that the economy should be the primary focus of analysis. Note that realism and liberalism are politics-centric theories of international relations.
Nonetheless, Marxism as it applies in international relations, specifically argues that the instability in the international system results from the different facets of class struggle such as the problems due to capitalism, exploitation of resources by the few, uneven distribution of wealth, and the institutionalization of inequality and injustice.
2. Functionalism: Functionalism is one of the contemporary theories of international relations that emerged from notions about the obsolescence of states or national governments as the primary actor in the international system or the “state” as a form of social organization.
The theory of functionalism specifically emerged during World War I and World War II, as well as the integration of Europe. Central to its argument is the rejection of realism through the promotion of an idea that global integration is a process arising from the realization of the common interests of states. This global integration creates a system with functions that are more important than the functions of individual actors.
3. English School: The English School is another contemporary theory of international relations that attempts to provide a lens for analysis by combining the principles of realism and liberalism. The theory intends to answer the following question: How to understand international relations by incorporating the cooperative aspect of liberalism into the realist conception of the conflicted nature of the international system?
Central to the argument of the English School is that there are three distinct spheres at work in international politics. These are the international system that is characterized by the power politics among state actors, the international society characterized by the institutionalization of shared interest and identity amongst states, and the world society characterized by the creation of global societal identities and arrangements based on the participation of individuals, non-state organizations, and ultimately the global population as a whole.
4. Feminism: Feminism in international relations theory is a broad term referring to different concepts and models patterned after a particular theory in feminism to analyze the international system and corresponding relationships. Feminist international relations theory argues that the concepts of power, dominion, and security stemming from other international relations theories are gender-biased. It also argues for the need to understand the role of women or the impact of gender dynamics in shaping the international system.
Other arguments include looking how the concept of masculinity shaped foreign policy and diplomatic relations, considering women as a group of actors in the international system, and the use of the concept of femininity in handling conflicts.
5. Green Theory: Green Theory focuses on international environmental cooperation. As one of the radical theories of international relations, it examines the international system outside the purview of major theories by focusing specifically on cross-boundary or inter-state problems concerning the ecology and environment.
One of the general assertions of Green Theory is that other theories of international relations are blind about the ecological problems, as well as the role of the environment in shaping the international system and corresponding interactions among different actors. A more specific argument asserts the need to respond to ecological problems as part of responding to the changes brought about by increasing global integration and interdependence.