States are units, not agents. To the extent that we accept that a structure of identities and interests also affects the behaviour of states, we are better able to treat states as purposive agents whose normative claims influence the definition of these identities and interests, Fabiano Mielniczuk writes.
Although the balance of power mechanism has a long historical and analytical lineage, it was only recently that the concept of polarity began to receive proper scientific treatment. In fact, the first “elegant” contribution to this concept appeared in Kenneth Waltz’s Theory of International Politics, published originally in 1979 , based on his analogy between microeconomics and the structure of the international system. In this work, Waltz considers that the structure is defined by its polarity, understood from the relationship between the accumulation of power within and the distribution of power among states. Polarity is defined in terms of the capabilities necessary to ensure survival in an anarchic environment marked by the security dilemma. Broadly speaking, capabilities refer to the territory, population, natural resources, and technology employed by states as “like-units” in their quest for survival. The states that concentrate the most capabilities are the “poles”, referred to here as polar states, and the distribution of capabilities occurs in two ways: bipolar, when two states concentrate capabilities, or multipolar, when three or more states concentrate capabilities. Since “unipolarity” would imply the imposition of a hierarchy in a system that is, by definition, anarchic, realists assume that there would be a natural reaction to a single pole, giving rise to bipolarity or multipolarity.
The most interesting aspect in this approach is its ability to predict the behaviour of states in bipolar and multipolar structures. In bipolarity, polar states attempt to overcome their adversaries through internal balancing — autarkically increasing their capabilities — rather than through external balancing — through alliances with other states. This does not mean that alliances do not exist. However, given the difference in capabilities between the polar state and its allies, its actions toward them are flexible, and the risk of an “overreaction” that would involve it in conflict with the other pole is low. In this structure, because there are only two main states, there is clarity about the adversary’s interests and the means at its disposal to achieve them, which reduces the risk of miscalculations. Therefore, bipolarity would be more stable. In multipolarity, because there are a greater number of polar states and a more balanced distribution of capabilities among them, the dominant strategy is external balancing. Given the number of poles, the possibility of diverse alliances is greater. Such flexibility, however, hides the rigidity of this strategy: as each state is more dependent on the others, the commitment to allies is greater. But the increase in the number of relevant units leads to the risk of miscalculation. That is why multipolar structures are more unstable .
These arguments have sparked numerous debates on the stability of bipolar and multipolar structures. Two contributions are particularly noteworthy. Mansfield suggests that, depending on the concentration of capabilities in bipolarity, external balancing strategies may be prioritised. If there is a significant power disparity between the two poles, and the disparity between the weaker pole and the other states is not as pronounced, this pole may choose to ally with stronger non-polar states in order to balance the power of the antagonistic polar state.
From the 2000s onward, things became more complicated due to the persistence of the American “unipolar moment”. The traditional balance of power view suggested that in the absence of a balancer, the polar state would tend to project its power over other states carelessly, leading to “overstretching”. This interpretation serves as a plausible justification for the phenomenon of the projection of Western liberal identity spearheaded by the United States across the globe, the most exemplary case being the expansion of NATO after the end of the Warsaw Pact. Such a decision on the part of US decision-makers would facilitate the decline of the unipolar order, driving Russia into the arms of China, as Waltz famously observed. This belief in the natural redistribution of power left scholars until recently with no theory capable of explaining whether unipolarity would be more or less stable .
Recently, Wohlforth proposed that stability in unipolarity occurs due to the exorbitant difference in status between the unipole and the other states, which would discourage any attempt to change the status quo. Here, status means the projection of the concentration of material capabilities in the symbolic dimension, as a kind of recognition by others of the unipole’s superiority. Thus, the other great powers and smaller states dare not challenge the unipole, which has the necessary means to guarantee stability. Monteiro , in turn, concluded that stability in unipolarity is impossible, and that the intensity of conflicts depends on the strategy adopted by the unipole. If it chooses to maintain the status quo in the distribution of the elements that constitute capabilities (territory, economy, military power, technology, etc.), there is a lower likelihood of conflict in the short term. This strategy is called defensive dominance. However, if the unipole chooses to alter the distribution of one of these elements (offensive dominance strategy) or ignores other states’ efforts to promote these changes (disengagement), conflicts arise more quickly and with more dangerous consequences. The conclusion is that unipolarity can endure, but it will always be prone to instability, as conflicts between the unipole and smaller states, and between great powers and medium-sized states are a reality.
These contributions to the relationship between stability and polarity in different structures have two problems. The first is that they are all snapshots of a given moment, and they need to assume the maintenance of a certain power configuration to make sense. They do not explain the shift from one structure to another, as the failure of these approaches to address the end of the Cold War revealed. However, such portraits are valuable in the sense that the comparison between the older and the more recent snapshots offers a clear description of how the international system has changed.
Based on this comparison, the international system can be described as follows: 1) Only the unipolar power is dominant in all the elements that define capabilities, and these elements are increasingly unevenly distributed among the other states; 2) The unipole and polar states have fewer capabilities relative to the other states than in the past, indicating that power is more diffuse in the system; 3) There are more nuclear states capable of deterring the unipole and polar states, but they are not counted as poles to define the structure; 4) The concentrations of capabilities vary in different degrees: a) from the United States (Unipole) to China (the would-be second Pole); b) from the United States and China to the other great powers (Russia, Japan, India, some European countries); c) from the other great powers to the emerging or middle powers (Brazil, Indonesia, Turkey, South Africa, etc.); d) from the emerging and middle powers to the remaining states.
Note that this is a description of the international system, not of its structure, because it really does not make sense, based on the traditional polarity theory, to assert that there are causal mechanisms of unipolar, bipolar, and multipolar structures acting on states’ behaviour simultaneously. Even so, if we observe the empirical reality, overstretching, overreaction, miscalculation, internal balancing, external balancing, offensive dominance, defensive dominance, disengagement, and status-driven conflicts might all be happening at the same time. To make matters worse, there are differences in the concentration of capabilities and there is scarcity of resources to accumulate capabilities, as the concern about energy transition or the need for rare earth minerals demonstrates . Besides the academic anxiety that such a meaningless description of reality brings to the theoretical debate, there are good reasons to fear that international politics has never gone through a phase with such great potential for disaster. How can we tame these emerging polarities?
The answer to this question is related to the second problem in the relationship between stability and polarity, something that has already been generally pointed out by constructivists: the material ontology of structure in realist approaches limits the explanation of change, since a causal relationship is inferred between states’ capabilities and behaviours . This limitation stems from the microeconomic model on which the structure is based, since it is defined as a mechanism that exerts unexpected effects on states, regardless of their will. Therefore, states are units, not agents. To the extent that we accept that a structure of identities and interests also affects the behaviour of states, we are better able to treat states as purposive agents whose normative claims influence the definition of these identities and interests. If this ideational-normative level is incorporated into the analysis, previously misunderstood phenomena, such as the BRICS, begin to make sense and even become exemplary elements for understanding the new order . After all, it seems clear that the BRICS are a grouping, among others, that emerged as a response to the duplicity of Western normative standards exposed over these 30 years of “rules-based order”. Perhaps the perceived shifts in polarities stem from this, and not simply from the struggle for survival. Perhaps such groups might play a relevant role in trying to tame the emerging polarities.
References:
Monteiro, Nuno P. 2011. “Unrest Assured: Why Unipolarity Is Not Peaceful”. International Security 36(3): 9–40.
Mansfield, Edward D. 1993. “Concentration, Polarity, and the Distribution of Power”. International Studies Quarterly 37(1): 105–28.
Midlarsky, Manus I., e Ted Hopf. 1993. “Polarity and International Stability”. American Political Science Review 87(1): 173–80.
Mielniczuk, Fabiano. 2013. “BRICS in the Contemporary World: changing identities, converging interests”. Third World Quarterly 34(6): 1075–90.
Waltz, Kenneth N. 2007. Theory of International Politics. Boston, Mass.: McGraw-Hill.
Waltz, Kenneth N. 2000. “Structural Realism after the Cold War”. International Security 25(1): 5–41.
Wendt, A. 1999. Social Theory of International Politics. Cambridge University Press.
Wohlforth, William C. 2009. “Unipolarity, Status Competition, and Great Power War”. World Politics 61(1): 28–57.
Wohlforth, William C. 2022. “Polarity and International Order: Past and Future”. Em Polarity in International Relations: Past, Present, Future, orgs. Nina Græger, Bertel Heurlin, Ole Wæver, e Anders Wivel. Cham: Springer International Publishing, 411–24.
