Within each perspective, different theories focus on different factors in international politics. The state is a key actor in international politics in many international relations theories. States are considered to be sovereign entities in the international system, meaning that they are not subject to the commands of others; they have independent control over themselves and their decisions. To be considered a state, an entity must have a defined territory, a stable population, and an effective government, and must be recognized by other states as having the capacity to enter into relations with them. Many internationl relations theories treat the state as a unitary actor in international politics. In other words, they personify the state, treating it as a nactor that has its own defined interests and chooses its own actions in the international systems. International institutions are also central actors in international politics for many international relations theories. International relations scholars define international institutions as sets of rules meant to govern state or international behavior. Rules, in this context, are conceived of as statements that forbid, require, or permit particular kinds of actions. An institution can be a formal organization that embodies particular sets of rules, but it can also be a treaty. Some international relations theories focus attention on the role that multinational corporations play in international politics. These corporations span state borders, connecting states together in important ways. Multinational corporations (MNCs) not only invest in other countries by building up operations within them but also acquire interest in foreign companies, or engage in mergers or join ventures with them. Multinational corporations lso trade with one another both within and across state borders, creating important economic connections between states. Some internationl relations theories focus on individuals and their ctions in order to explain various events in international politics. Individual state leaders and their personal characteristics influence their state’s foreign policy choices and hence international relations. Non-elite individuals acting alone or in groups can also influence interntional politics. Factors that influence outcomes in international politics an also be more conceptual in nature. For example, some theories focus on the role that the international system plays in affecting outcomes. The idea that the international system can influence international politics means that characteristics of a set of states taken together, and their relationships, contribute in important ways to international relations. Two other conceptual factors that some international relations theories focus on are identities and norms. An identity is a sense of self, based on certain qualities and beliefs that serve to define a person or group. Group identities can be associated with the state and particular state characteristics. They can also be associted with ethnicity, language, and religion. Norms are collective expecttions for their proper behavior of actors with a given identity. In the international system, norms can provide expectations bout the proper behavior of states, such s respecting human rights and being transparent on international security issues.
Realism is a fundamental perspective from which some theorists approach the study of international politics. The factors on which realists focus most attention are the state and the international system. For most realists, states are unitary actors that rationally pursue their own national interests (the protection of territory and sovereignty) when they act within an anarchic international system. This idea of anarchy refers to the fact that in the international system there exists no hierarchically superior, coercive authority that can create laws, resolve disputes, or enforce law and order. Given this condition of anarchy, realists argue that states can rely only on themselves to protect aginst attacks or other forms of coercion from other states in the system. Their most important interest is therefore to increase their power–the material resources necessary to physically harm or coerce other states. Realists see states as increasing their power in two possible ways: (1) through war (and conquest) or (2) by balancing against powerful states by taking actions to offset their power and thus fend off a potential attack. According to realists, states’ main focus is their security.
International politics is best characterized as a struggle for power. In this context, both military and economic power matter. Because of this constant struggle for power, realists argue that states are concerned with relative gains. In contrast to absolute gains, which refers to how much one state gains for itself, relative gains refers to how much more one state gains over another. When one state gains relative to another state, it can feel more secure beause it can better fend off an attck from the other, or can more successfully launch its own attack against the other. Even if both states can gain in absolute terms from cooperative interactions, the state that gains most relative to the other has a security advantage. Despite being able to gain something in absolute terms, the state that would lose in relative terms has an incentive not to cooperate with the other. Coopertion is therefore difficult to achieve, and tensions between states are likely to result. This concern for relative gains can lead to what realists call a security dilemma. A state working to ensure security from attack is driven to acquire more and more power. This, however, renders other states more insecure, which drives them to cquire more power. This mkes the first state less secure, and it thus works to gain more power. And the spiral continues. The security dilemma, then, results in a permanent condition of tension and power conflicts among states, even if none actually seek conquest and war. In other words, security is a zero-sum game. Relative gains concerns and the security dilemma are important explanations for costly arms races. One focus of many realists is the idea of managing power through “balancing”. This can take two forms: internal or external. Internal balancing refers to a state’s building up its own military resources and capabilities in order to be able to stand against more powerful states. External balancing refers to allying with other states to offset the power of more powerful states. A relative balance can deter both sides from engaging in an attack, thus helping to prevent war. While realism appears to offer clear policy prescriptions, not all realists agree on what an ideal foreign policy might look like. In particularly, a divide exists between defensive and offensive realists. Defensive realists observe that few, if any major wars in the last century ended up benefiting the state or states that started them. Threatened states, they argue, tend to balance against aggressors, invariably overwhelming and reversing whatever initial gains were made for the state that started the war. Offensive realists, on the other hand, argue that conquest can yield significant benefits to a stte by creating a reputation for a willingness to use force. That reputation can help a state get others to do what it wants for fear of war being waged against them as well. The logic of bandwagoning is that the more power you have, the more power you get. Conquest, in other words, pays.
Realism, as a general perspective, encompasses a family of related arguments that share common assumptions and premises. It is not itself a single, unified theory. Among ther various reinterpretations of what is referred to as “classical realism,” the most important is neorealism (or structural realism). Neorealists propose general laws to explain events: they simplify explanations of behavior in anticipation of being better able to explain and predict trends. While traditional realists attach importance to the characteristics of states and human nature, neorealists give precedence in their analyses to the structure of the international system as an explanatory factor. Neorealism advances two normative arguments and one theoreteical argument. The first normative argument is that we need theory to understand international politics and the second is that neorealism explains international politics since 1648, the date scholars cite for the advent of the Westphalian state system. The amount of peace and war in an anarchic international system depends critically on the distribution of power, described in terms of system structure. The distribution of power in the international system can be described as hving one of three possible forms: (1) unipolar, where one state in the system has sufficient power to defeat all the others combined aginst it; (2) bipolar, where most of the system’s power is divided between two states or coalitions of sttes; and (3) multipolar, in which power is divided among three or more states or coalitions of states. According to neorealists, the structure of the systme and the distribution of power within it, rather than the characteristics of indivudla states, determine outcomes. Some realists argue that the closer the overall distribution of power approaches to unipolarity, the greater the likelihood (but never the certainty) of peace. Balance-of-power theoriests, in contrast, would highlight the importance of a bipolar system for increasing the likelihood of peace, as the bipolar system represents a basic balnce of power between the two most powerful states.
Other interpretations of realism have also been developed. Dynamism is history as a series of cycles–cycles of the birth, expansion, and demise of dominant powers. Wheres classical realism offers no satisfactory rationle for the decline of powers, the answer from one internpretation is in economic power. Hegemons decline because of three processes: (1) the tendency for the returns from controlling an empire to decrease over time; (2) the tendency for economic hegemons to consume more and invest less over time; and (3) the diffusion of technology through which new powers challenge the hegemon.
What unites the various realist theories is their emphasis on the unitary state in an anarchic international system, the importance of power and the ability to use force as en effective tool of foreign policy, and the existence of the threat of war that can be managed but never done away with.
The basis of liberalism is firmly embedded in the belief in the rationality of human beings, the notion that humans are inherently social, living and working in groups, and that through learning and education, humans can develop institutions capable of ensuring and advancing human welfare.
Neoliberal institutionalism arose based on the observation that states in the international system actually cooperate most of the time. This is contrary to the realist predictions that cooperation is very difficult for states to achieve because of their concern for relative gains and the existence of the security dilemma. One answer to why we see so much cooperation likes in the idea of complex interdependence, which has three components. First, states are connected through multiple channels, not just through direct formal interactions. Informal interactions between governments often take place, and actors like multinational corporations span state borders, connecting states in important ways. Second, there is not a hierarchy of issues. States re concerned not only about security but also about other issues on which they share common interests. Third, the result is a decline in the use of military force. The assumptions of neoliberal institutionalism are the same as those of realism–states are key unitary actors in international politics that rationally pursue their own self-interest in an anarchic international system. Yet even though neoliberal institutionalists accept these realist assumptions, they argue that states can cooperate. Neoliberal institutionalists posit that cooperation arises because states are engaged in continuious interactions and are not solely focused on relative gains. They care bout absolute gains as well. Moreover, states focus not only on security but also on other issues on which they might shre common interests. Trade and the environment are key examples. When states care about absolute gains, the gains from cooperative interactions become a key part of states’ interests. When states interact over time, the gains from cooperation can accumulate and thus overcome their incentives to exploit the others’ cooperative actions for their own short-term gain. This is particularly true with regard to nonsecurity issues such as economics, in which gains from cooperation in trade and investment can be had by all. Reciprocity over time can help sustain this incentive, especially when complex interdependence charactgerizes states’ relationships and there are multiple channels and multitple issues in which reciprocity can be implemented. Power, therefore, does not rest solely on military might. Economic and social power also matter. According to neoliberal institutionalists, international institutions–both organizations and treaties–play a key role in international politics by fostering these cooperative interactions. International organizations provide a guaranteed framework for interactions, thus creating a situation in which continuous interaction is expected and reciprocity is fostered. International treaties also create expectations of repeated interactions over time. Neoliberal institutionalists arrive at the same prediction that other liberals do–cooperation–but their explanation for why cooperation occurs is different. For classical liberals, cooperation emerges from humanity’s establishing and reforming institutions that permit cooperative interactions and prohibit coercive actions. For neoliberal institutionalists, cooperation emerges because when actors have continuous interactions with each other, it is in their self-interest to cooperate.
Other branches of liberal theory do not treat the state as a unitary actor. They argue that state behavior at the international level is influenced in important ways by the domestic level. They have a “bottom up” view of international politics. These liberal theories share several assumptions. First, they argue that the key actors in international politics are individuals and private groups such as unions, nongovernmental organizations (NGOs), and corporations. Second, states’ actions represent some subset of those individuals and private groups. It is the interests of this subset of domestic society that define states’ preferences and shape their actions. Third, state behavior is defined by the configuration of state preferences, rather than the configuration of state power. When state’s undelying preferences are compatible, cooperation is likely to result. When they are at odds with one another, there is a high probability of tension and conflict. The substance and depth of cooperation or conflict depends on the constellation of states’ preferences.
Other important liberal theories highlight three key factors that can contribute to peace: democracy, economic interdependence, and international institutions.
Liberal theories are united by their assumption that actors in international politics are largely rational, that cooperation is possible and more likely than realists posit, and that states focus on issues beyond just security and survival.
Constructivism explains events in international politics through a focus on norms and identities–both of individuals and of states. For constructivists, the objects of study in interntional relations should be the identities of ctors, and the norms and practices of individuals and groups that stem from those identities. The relationship between different identities is also an important facet of undestanding international politics from the constructivist perspective. States’ identities can be convergent, meaning that those states shre similar characteristics and ideals, or they can be divergent, meaning that they do not share similar characteristics and ideals. This difference does not men that states necessrily have interests and idels tht are opposed to one another, but they could. Understanding the relationship between different identities is of central importance in international politics today. In addition to focusing attention on the role of norms and identities, constructivism offers the major theortical proposition\ that neither objects nor concepts have any necessary, fixed, or objective meaning. Instead, their meanings are constructed through social interaction. Identities are similarly socially constructed. State behavior thus depends not on the objective reality of a situation but on our subjective interpretation of that reality. An important part of that social construction of identities (and the resulting behavior) is our discourse. How we choose to talk about ourselves and others influences our interpreation of our recspective identities, as well as others’ interpretations of those identities. Therefore, in addition to how we act toward others, how we choose to talk about and frame our identities important for understanding how those identities (and the resulting behvior) come to be formed. Constructivists argue tht it is not only states’ behaviors that are shaped by beliefs about themselves and others, but also states’ very interests. For constructivists, states’ interests are the result of their socially constructed identities. Moreover, those identities and interests are not fixed. They can change as experience, discourse, and practices change. This stands in contrast to relist and liberal approaches to the study of international relations, which view state interests as based on purely material factors. Overall, constructivists dispute the idea that material structures have a necessary, fixed, or inherent meaning. The political structure of the international system (that is, whether the distribution of power is unipolar, bipolar, or multipolar) cannot tell us much of interest. It does not predict whether two states will be friends or enemies, whether they will recognize each other’s sovereignty, whether they will have revisionist or status quo ideals, and so on. It is the identities of states nd the reltionship between their identities, along with the norms that stem from those identities, that matter most. Constructivists do aling with realists and liberals in that they view power as important. However, whereas realists and liberals primarily see power in material terms (military, economic, or political), constructivists also see power in discursive terms–they focus on the power of ideas, culture, and language. In some constructivist theories, power rests in the ability to persuade when deliberating or arguing with others. Other theories invoke the idea of legitimacy as an important source of power. States may alter their actions so other members of the international community will view them as legitimate. These arguments bout persuasion and legitimacy lead to the idea of soft power–the power of a state to attract states to change their behavior based on the legitimacy of its values or policies, rather than having to coerce them into doing so. In other words, the legitimcy of one state’s actions can help it persuade others to adopt similar behavior. Constructivist theories also offer explanations of chnge that differ from those of relism and liberalism. Change can occur through diffusion of ideas or the interntionalization of norms, as well s through socialization (the process through which one adopts the identities of peer groups). These explanations help us understand tht ideas are spread both within a national setting and cross-nationally. This is how democracy is diffused, how ideas about human rights protection have been internationalized, and how states such as the new members of the European Union become socialized into the community’s norms and practices. Put another way, realism and liberalism both have a more difficult time explaining the advent, spread, and real-world impact of ideas and norms such as taboos against land mines or the “responsibility to protect”.
—July 2025
Lance Jones 