Theories of international relations often thrive on their ability to explain broad patterns of state behavior. Neorealism, in particular, has long been regarded as one of the most enduring and influential lenses for analyzing states’ actions within the field of international relations. The core works of Kenneth Waltz and John Mearsheimer, representing defensive and offensive neorealism respectively, aim to explain state behavior through the lens of power, security, and a common anarchic international system. Yet, when applied to different global regions, such as the case studies of the Arctic and the South China Sea, their theoretical coherence and applicability start to fracture. Both scholars provide compelling but broad insights into why states act the way they do, but neither framework fully accounts for the nuance and differences between different regions. This is particularly clear given the involvement of the same great powers – the United States and China. This article explores that inconsistency, arguing that Waltz nor Mearsheimer’s models falter when tested against these contrasting geopolitical environments.
The Arctic and the South China Sea present two vastly different theaters of geopolitical competition, yet involve the same principal actors – the United States and China. If neorealism, as a school of thought, is to claim universal validity then it must explain not only why states behave as they do in one region but also why those same behaviors are different elsewhere. The inability of either theory to achieve this exposes a core weakness in their otherwise robust frameworks: a regional blind spot that undermines both branches individually and neorealism overall.
Kenneth Waltz’s defensive realism, outlined in Theory of International Politics, suggests that states seek security rather than power for its own sake. According to Waltz, states actions are primarily driven by the need to maintain their survival within a naturally anarchic international system. This leads to a balancing behavior, for example through internal measures such as military buildup or external alliances, to prevent any single state from becoming overly powerful and threatening the others’ stability. This assumption helps explain the Arctic’s more cooperative tendencies, where great powers like the U.S., Russia, and even China engage in diplomatic mechanisms through institutions like the Arctic Council. Competition here is primarily through scientific advancements and economic means such as resource management. The harsh environment, economic barriers, and lack of widespread militarization validate Waltz’s emphasis on balance and restraint.
Mearsheimer’s offensive realism, by contrast, assumes that states pursue as much power as possible, not just to survive but to achieve maximum power within their region, as this will ultimately secure their safety. In The Tragedy of Great Power Politics, Mearsheimer argues that because states can never be sure of others’ intentions, the safest path is to dominate the region in which they exist to prevent rival powers from emerging elsewhere. This framework neatly explains geopolitical conditions in the South China Sea. China’s island-building campaigns constitute the militarization of contested territories like the Spratly and Paracel Islands. China’s rejection of international arbitration (specifically, the Hague’s Permanent Court of Arbitration ruling against China’s claims) reflects a concerted effort to push US influence out of the region. The US, in turn, bolsters regional allies like Japan and the Philippines, using its naval forces to conduct freedom of navigation operations (FONOPs) to show its unwillingness to concede power dynamics in the region to China’s dominance.
At first glance, each theory seems to neatly explain one region’s dynamics with Waltz’s balance in the Arctic, and Mearsheimer’s power competition in the South China Sea. But why don’t these dynamics hold across both regions? The fundamental problem emerges when we step back and realize that the same great powers, the United States and China, behave in entirely different ways depending on the region. Waltz’s model explains the Arctic, and Mearsheimer’s model explains the South China Sea- but neither explains both. This exposes a key flaw: why do these two states, operating under the same global conditions, pursue economic means of influence in one region and military confrontation in another?
Take China, for example, In the South China Sea. It aggressively asserts sovereignty through military infrastructure, economic coercion, and the legal rejection of international rulings. Mearsheimer would argue this is a classic example of regional hegemony-seeking behavior, as China wants to push the US and any other potential geopolitical leaders out to secure its dominance and long-term survival. Yet in the Arctic, China plays a remarkably different game. It presents itself as a “near-Arctic state” in its Arctic strategy papers. It has no permanent military presence in the Arctic. Its primary focus is on scientific partnerships, such as the Yellow River Station in Svalbard, and economic investments in Russia’s Northern Sea Route such as its partial ownership of the liquified natural gas project Arctic-2. It observes the norms of the Arctic Council, avoiding military posturing, much like the council itself which largely oversees trade disputes and environmental issues, not war talks. If Mearsheimer is right that China’s ultimate goal is power maximization and ultimate dominance, why would it not replicate its South China Sea behavior in the Arctic?
Similarly, the US appears assertive in the South China Sea, engaging in naval patrols, strengthening alliances, and openly confronting China’s territorial claims- behavior consistent with Mearsheimer’s model of preventing the rise of a regional peer competitor. But in the Arctic, Washington takes a far softer stance. The Department of Defense’s 2024 Arctic Strategy adopts a “monitor-and-respond” approach, despite explicitly naming China as a geopolitical threat in the region. This strategy focuses on enhancing domain awareness, engaging with allies to uphold defense and deterrence, and maintaining a calibrated military presence through regular operations. The goal here is to ensure the Arctic remains a secure and stable region without escalating military tensions. The U.S. approach to Arctic security also emphasizes a non-military, Coast Guard-led presence focused on law enforcement, search and rescue, and environmental protection.
These non-escalatory actions help to position the US as a stabilizing force rather than a provocative one. This strategy reinforces the US commitment to maintaining regional security through maritime governance and cooperation, avoiding the escalation that any traditional military buildup may provoke. It aligns with Waltz’s defensive stance, that states avoid excessive military confrontation in hopes of reliable security. However, if Waltz’s defensive realism holds in the Arctic and states do indeed prioritize survival, why does the US still project itself militarily in the South China Sea where there is no direct presence of its citizens?
This contradiction – that the same states behave in ways that conform to one neorealist framework in one region but defy it in another – reveals that both theories suffer from regional shortsightedness. Neither framework accounts for why states strategically adapt to different regional environments, despite facing the same systemic pressures. The answer, perhaps, lies in what Waltz and Mearsheimer overlook: the role of region-specific constraints and incentives. Both assume a uniform international structure, yet regional subsystems create unique strategic landscapes that push states to behave differently.
In the Arctic, extreme environmental and economic barriers make military escalation not just costly but counterproductive. Ice coverage, logistical challenges, and limited population centers reduce the sustainability and value of any territorial control. The Arctic Council’s institutional strength, which is rooted in scientific diplomacy and indigenous representation, also creates a somewhat normative barrier to aggression. States still pursue influence in the region, agreeing with a general realist assumption, but they do so through other routes. These manifest primarily as economic policies (e.g., energy projects) and scientific partnerships rather than military posturing.
The South China Sea, in extreme contrast, is an economic and military chokepoint. Almost 60% of global maritime trade passes through its waters, and the seabed holds untapped energy reserves. This trade also flows through tight vital chokepoints, such as the Strait of Malacca and the Luzon Strait. Control over these geographic features gives states massive strategic advantages. This economic attraction, combined with densely packed states and historical sovereignty disputes, fuels competition. The fragmented nature of the region also eases offensive capabilities; militarising small islands is easier than large land mass. There is further incentive for this, given the region’s open waters provide relatively few land barriers. States are therefore required to proactively construct maritime borders, as they are not reinforced by natural geographic barriers.
What neither Waltz nor Mearsheimer fully capture is how these regional factors shape strategic options. Their theories treat the international system as on single system, wherein the theories that justify the actions of states are static. However, states don’t engage with “the system” in an abstract and uniform – they engage region by region, adapting to local constraints. The Arctic and South China Sea cases demonstrate a critical flaw in neorealism’s two most influential variants: Waltz’s defensive realism and Mearsheimer’s offensive realism. Both theories successfully explain one region’s behavior but fail to extend that logic to the other. This is despite the same geopolitical powerhouses operating within the same two theaters. The core issue is that neither model accounts for regional variation. They assume a uniform international structure, where states respond to systemic pressures in predictable ways. Yet, the strategic environment isn’t uniform.
The Arctic incentivizes restraint through its harsh environmental barriers, economic limitations, and cooperative institutions. Meanwhile, the South China Sea, on the other hand, rewards aggressive posturing due to its demography, economic importance, and strategic geography. The same states behave differently because the regional landscapes force them to adapt, which is a clear reality that neorealism as an entire theoretical school overlooks.
This doesn’t mean Waltz and Mearsheimer’s theories should be entirely discarded. In fact, the opposite. Both of the cases examined here illustrate that offensive and defensive neorealism can adequately explain contemporary cases, even if not universally. Each provides valuable insight into the motivations of states under anarchic conditions. However, their failure to reconcile regional variation suggests the need for a more adaptable neorealist framework, one that retains the systemic logic of power and security competition but integrates regional constraints as a key variable, if not the primary variable.
A regionally adaptive neorealism would acknowledge that states are rational, but their strategies are shaped not just by the international system’s structure but also by the unique economic, geographic, institutional, and population features of specific regions. This approach would help explain why the same states, each facing the same systemic pressures within the same geopolitical landscape, pursue power differently depending on where they are. It’s not that Waltz or Mearsheimer are wrong; it’s that their models lack the flexibility to account for the complex, region-specific realities shaping a state’s behavior. In this sense, states may act on an offensive-defensive spectrum, displaying the traits posited by both schools depending on different regions.
Recognising the dynamic nature of neorealism as a whole grants room to emphasise the fluidity of impacting factors, thereby providing a more accurate predictive tool. Regional shifts like the Arctic’s melting ice, for example, may result in shifting tactics, with increased competition to secure new global chokepoints like the Northern Sea Route. On the other hand, population growth and resource demand may push the South China Sea further towards the offensive end of the spectrum. Ultimately, neorealism’s greatest flaw isn’t in its core assumptions about power and security but in its inability to recognize that the “international system” is not experienced in a consistent manner. The Arctic and South China Sea reveal that regional dynamics matter and any theory claiming universal applicability must account for that.
Further Reading on E-International Relations
- Continuity and Change: China’s Assertiveness in the South China Sea
- The Role of United Nations Convention on the Laws of the Sea in the South China Sea Disputes
- Is China Under-Exploiting One Legal Avenue in the South China Sea?
- Contesting American Power: Beijing’s Challenge in South China Sea Disputes
- The Role of ASEAN in the South China Sea Disputes
- US Policy in the South China Sea Across Three Administrations
