Cyberspace

In recent decades, technological advances driven by scientific breakthroughs have opened a new venue for human interaction: cyberspace (Choucri Reference Choucri2012, 6). The prefix “cyber” encompasses “a variety of digital, wireless, and computer-related activities” (Nye Reference Nye2017, 46). The term “space” means “domains of interactions” that have their own resources, power sources, and actors seeking to increase their leverage. While IR theory focuses on interstate relations conforming with the notion of “territoriality,” cyberspace emphasizes nonterritoriality (Choucri Reference Choucri2012, 5–6).

As a nascent domain, the study of cyberspace is marked by conceptual diversity (Lindsay Reference Lindsay2017, 494). While cyberspace can structurally be divided into four layers (e.g., physical and informational layers), many of these layers are only concerned with its technical architecture and thus are not very relevant to IR scholars, who are fundamentally interested in how cyberactors use this domain to pursue power and strategic interests. This is important because cyberinsecurities emerge due to the combination of the structural design of cyberspace and the activities, interests, and motives of actors (Choucri and Clark Reference Choucri and Clark2018, 39–52). Therefore, I define cyberspace as a global, operational, political, and man-made domain where human interactions are enabled by interconnected computing devices to create, store, exchange, modify, and exploit electronic information, and to facilitate communication between users (Akdağ Reference Akdağ2017, 102; Choucri and Clark Reference Choucri and Clark2018, 33; Nye Reference Nye2011, 122).

Unlike natural domains, cyberspace requires human maintenance (e.g., installing fiber-optic cables) to function. Cyberspace is technologically malleable and replicable: as one platform is destroyed, another can be opened swiftly. As a global venue unconfined by geography, cyberspace has shifted the dynamics of geopolitics and shaped states’ foreign policies. While cyberspace has physical, border-traversing components that subject it to some restrictions (e.g., governmental regulations), geographical constraints are dramatically removed in the new domain. Its interconnectedness enables instant and persistent contact, which lowers the costs of transportation and deploying force in this sphere (Harknett and Smeets Reference Harknett and Smeets2022, 544; Zook, Devriendt, and Dodge Reference Zook, Devriendt and Dodge2011, 94). The nongeographical property of the domain allows worldwide participation, as entering cyberspace requires only a computing device and an internet connection, making it easily accessible and participation cost effective (Choucri Reference Choucri2012, 4; Harknett and Smeets Reference Harknett and Smeets2022, 543–44; Sheldon Reference Sheldon2011, 96–98).

Cyberspace is “structured” by interconnectedness, not by the “segmentation” characteristic of “episodic,” “potential,” or “imminent” state-to-state territorial contact (Fischerkeller, Goldman, and Harknett Reference Fischerkeller, Goldman and Harknett2022, 30–31). This interconnectivity creates continuous contact among states, potentially affecting national power dynamics. This “constant contact” is a structurally imposed “condition” (Fischerkeller and Harknett Reference Fischerkeller and Harknett2019, 274), substituting the traditional understanding of temporality with the “near instantaneity” of cyberinteractions (Choucri Reference Choucri2012, 4).

CPT treats interconnectivity, reconfigurability, and continuous contact in cyberspace as key structural features critical to understanding how states pursue cybersecurity and national interests. These features create a “cyber strategic environment” where security is scarce, and where states are structurally incentivized to persistently seize and maintain the initiative to (re)establish favorable security conditions in and through cyberspace (Fischerkeller, Goldman, and Harknett Reference Fischerkeller, Goldman and Harknett2022, 24). Initiative persistence can maintain or alter the interstate balance of power through cumulative strategic effects generated by exploitative actions over time. For CPT, the cyberenvironment is noncoercive because it favors exploitation as the dominant behavior and the “primary route towards gain” (Fischerkeller, Goldman, and Harknett Reference Fischerkeller, Goldman and Harknett2022, 7). “Cyber faits accompli” (internal balancing) and “direct cyber engagement” (external balancing) are key behaviors states manifest to exploit vulnerabilities and opportunities. This prompts “agreed competition” wherein “competitive interaction” that is “inclusive of operational restraint” and “exclusive of operations” short of armed-conflict equivalence emerges as the dominant dynamic in cyberspace (Fischerkeller, Goldman, and Harknett Reference Fischerkeller, Goldman and Harknett2022, 50–59).

While CPT and modified OR draw distinct implications and prescriptions from the structural features of cyberspace (e.g., the logic of exploitation versus the logic of expansion), to which I will return, both converge on the strategic saliency of the domain. Cyberspace presents states with sufficient incentives and opportunities to gain strategic advantages over adversaries, potentially shifting the balance of power. This has made cyberspace an arena for power politics and competition across two dimensions: (1) the management of cyberspace; and (2) cybersecurity (Brandes Reference Brandes2013, 90–93; Choucri Reference Choucri2012, 4–9; Ebert and Maurer Reference Ebert and Maurer2013, 1058–64; US Department of Defense 2018). The clash over governance reflects a tension between the US-sponsored multistakeholder model, which promotes an open and decentralized management of the internet, and the multilateral model supported by authoritarian regimes (e.g., China), which demands more control over the internet (Gao Reference Gao2022, 15–16; Hill Reference Hill2014, 26–30). The cybersecurity dimension concerns competition between great powers to revise the cyber status quo by reallocating resources, shifting security dynamics, and amending governing rules (Ebert and Maurer Reference Ebert and Maurer2013, 1054–58). Cybersecurity is most fundamentally concerned with the ability of a state to protect its cyber and kinetic components (e.g., its servers and economy) from threats (Choucri and Clark Reference Choucri and Clark2018, 139). Cybersecurity competition mostly involves economic espionage, intelligence gathering, digital sovereignty, and the militarization of cyberspace (Harold, Libicki, and Cevallos Reference Harold, Libicki, Cevallos, Harold, Libicki and Cevallos2016, 9). When states struggle for cybersecurity or cyberpower, politics naturally ensues (Choucri Reference Choucri2012, 4–9).

Cyberpolitics

While the global and operational characteristics of cyberspace are well recognized, its political saliency has been overlooked. It is an arena wherein states negotiate, bargain, contend, compete, and engage in conflict over resources or institutional processes—the fundamentals of power competition. This fact, coupled with the growing awareness of cyberthreats, the involvement of multiple actors, attribution problems, and perceived offense dominance, has elevated cyberissues to high politics, which is closely linked to national security matters (Choucri Reference Choucri2012, 4–9; Ebert and Maurer Reference Ebert and Maurer2013, 1054–56; Limnéll Reference Limnéll2017, 42–43).

Yet cyberpolitics lacks a precise definition due to its infancy. It can be conceptualized as a process of politics driven by human interactions to authoritatively determine “who gets what, when, and how” in cyberspace—a new contested domain with its own methods and procedures. In cyberpolitics, actors struggle to influence or control resources and the behavior of others. For example, a state’s cyberdeterrence engagements involve cyberpolitics because they seek to shape an opponent’s payoff calculation within cyberspace. Because politics implies some degree of struggle, actors’ relative cyberpower is the essential determinant of their political interactions in cyberspace (Choucri Reference Choucri2012, 4–9; see also Cavelty Reference Cavelty2018, 304; Limnéll Reference Limnéll2017, 42–43; Valeriano and Maness Reference Valeriano, Maness, Brown and Eckersley2017, 261).

Cyberpower

Notwithstanding its growing importance, the concept of cyberpower remains undertheorized in realist IR scholarship, with most analyses limited to US strategy and policy (Cavelty Reference Cavelty2018, 305). Nevertheless, the literature offers workable definitions of cyberpower. Some scholars conceptualize it as “the ability to apply typical forms of control and domination in cyberspace” (Valeriano and Maness Reference Valeriano, Maness, Brown and Eckersley2017, 261–66).

Other studies have addressed the multidimensional aspects of cyberpower using various conceptual, theoretical, and normative perspectives to establish a structured analysis. Joseph Nye (Reference Nye2011, 123) defines cyberpower as “the ability to obtain preferred outcomes through use of electronically interconnected information resources of the cyber [domain].” Nye also describes three different manifestations of cyberpower—restrictive cyberpower, deterrent cyberpower, and compellence. Restrictive cyberpower leaves limited choices for adversaries via defensive means (e.g., firewalls), whereas deterrent cyberpower seeks to mold actors’ preferences to avoid harmful actions (e.g., using retaliatory threats to deter). Compellence, however, aims to force adversaries to do something against their will. The purpose of Stuxnet, for example, was to make Iran concede to the US’s will (Nye Reference Nye2011, 122–32; Valeriano, Jensen, and Maness Reference Valeriano, Jensen and Maness2018, 106). John Sheldon (Reference Sheldon2011, 96–97) defines cyberpower as “the sum of strategic effects generated by cyberoperations in and from cyberspace.” The purpose is to gain advantages over adversaries, reduce their capacity to understand the strategic environment, and achieve foreign policy objectives.

David Betz and Tim Stevens (Reference Betz and Stevens2011, 145–53) offer an alternative conceptual framework that identifies four dimensions of cyberpower, challenging Nye’s direct, centralized, coercive form of power relations with their focus on indirect and more diffused institutional, structural, and productive forms of cyberpower. While these typologies exhibit “forms of dominations to the exclusion of ‘power to,’” Alexander Klimburg’s (Reference Klimburg2011, 43–44) Integrated Capability Model stresses the importance of the nexus between cybersecurity and cyberpower. A country’s cyberpower is also measured by its ability to defend itself against cyberthreats and achieve security in cyberspace (Cavelty Reference Cavelty2018, 309–10). Frameworks that take defensive capabilities into account paint a more accurate picture of the interstate balance of cyberpower and reveal a paradoxical situation in which nations with the greatest cyberoffensive power are often the most vulnerable (Valeriano and Maness Reference Valeriano and Maness2015, 25).

As the discussion above indicates, cyberpower is imprecise, multifaceted, and heterogeneous. Its definition varies depending on the theoretical lenses with which one seeks to understand and explain the nature of power relations in cyberspace. Liberal IR theory ties cyberpower to institutional mediation, but liberal institutions are either nonexistent or underdeveloped in this sphere (Craig and Valeriano Reference Craig, Valeriano, Davide Orsi and Nurnus2018, 88; Keohane Reference Keohane2020, 2–6). Constructivist and poststructuralist theories of IR challenge conventional explanations of the nature of power in cyberspace. Instead they highlight different sources of power such as productive power, yet cyberpower produced through language and social interactions between states and between state and nonstate entities is harder to quantify due to its indirect and diffused nature.

A realist explanation of cyberpower, as reflected in Nye’s model centered on coercive power, remains the most viable conceptual tool to use, given its relatively measurable and attributable characteristics (Cavelty Reference Cavelty2018, 308–16). Nevertheless, accurately assessing both a state’s cyberpower and the interstate balance of power in cyberspace remains challenging due to cyberpower’s stealthy characteristics and its ubiquity—that is, its ability to exert an effect across multiple domains beyond cyberspace (Sheldon Reference Sheldon2011, 99–100; see also Valeriano and Maness Reference Valeriano, Maness, Brown and Eckersley2017, 266).

However, not all scholars believe that cyberpower can be coercive, a discussion I will return to below. Nevertheless, many concur that cyberpower is a relatively flexible and useful means of gaining strategic advantages over rivals (Choucri and Clark Reference Choucri and Clark2018, 364). In what forms is cyberpower projected and accumulated? The answer rests with the concept of cyberconflict.

The Rise of Cyberconflict and Cyberwar

The concepts of cyberconflict and cyberwar began their rise to prominence with John Arquilla and David Ronfeldt’s 1993 article “Cyberwar is Coming,” which was written within the strategic context of the mid-1990s and heralded a new era in strategic thinking—a revolution in military affairs (Arquilla and Ronfeldt Reference Arquilla, Ronfeldt, Arquilla and Ronfeldt1997, 27–31). Since then, discourse about cyberwar has gradually shifted from its disruptive effects on information and communication technologies (ICTs) to its potential to cause the physical destruction of critical infrastructure, especially after the Stuxnet incident in 2010 (Harknett and Smeets Reference Harknett and Smeets2022, 536–37). Jason Healey (Reference Healey and Healey2013, 17–20) dubs this new phase the “militarization” period of cyberwarfare; its emergence represents a paradigm shift from the information warfare of the 1990s to cyberwar, and marks the growing strategic saliency and destructiveness of cyberoperations in the US (Haizler Reference Haizler2017, 32–37).

Existing conceptualizations of cyberconflict exhibit little divergence. For example, Healey (Reference Healey and Healey2013, 15) defines cyberconflict as “when nations and non-state groups use offensive or defensive cyber capabilities to attack, defend, and spy on each other, typically for political and other national security purposes.” Others conceptualize it as “the use of computational technologies for malevolent and destructive purposes to impact, change, or modify diplomatic or miliary interactions” (Valeriano and Meness Reference Valeriano and Maness2015, 21). Although Healey’s definition places greater emphasis on the defensive aspects of cyberconflict, the fundamental distinction between these definitions lies in the actors involved. The latter implies that cyberconflict is contested by states, as “diplomatic or military interactions” are the province of states, and nonstate actors have a limited capability to exert a meaningful effect on these interactions—a definition consistent with Valeriano and Meness’s state-centric approach (Valeriano, Jensen, and Maness Reference Valeriano, Jensen and Maness2018, 2–17).Footnote ⁴

In cybersecurity scholarship, cyberconflict serves as an umbrella term for “cyberwar,” which is misused as a broader concept due to the disproportionate attention that policy and academic circles give to destructive cyberoperations (Harknett and Smeets Reference Harknett and Smeets2022, 534; Healey Reference Healey and Healey2013, 14). More inclusive in scope, cyberconflict encompasses almost all cyberstrategies or politically motivated cyberactivities affecting national security (Craig and Valeriano Reference Craig, Valeriano, Davide Orsi and Nurnus2018, 87; Valeriano and Maness Reference Valeriano, Maness, Brown and Eckersley2017, 262).Footnote ⁵

Scholars theorize three generic cyberstrategies: disruption, espionage, and degradation. States employ these for various purposes, such as shaping the behavior of other actors through coercion and improving their relative power. Disruption tends to be unsophisticated and aims to influence the decision making of a target through harassment (e.g., the defacement of the Georgian government’s websites during the 2008 Russia–Georgia conflict). Cyberespionage, however, is stealthier and more sophisticated. It aims to achieve strategic advantages over adversaries and shift the interstate balance of information by infiltrating their computerized systems to gather intelligence (e.g., China’s attempts to steal the F-35 design plan). Unlike cyberespionage, cyberdegradation aims to mold the payoff structure of opponents by destroying their essential capabilities. Degradation is more advanced, resource intensive, damaging, and coercive in nature. Cyberwar falls into this category and may cross the threshold for “armed conflict,” potentially influencing interstate power balances (Harknett and Smeets Reference Harknett and Smeets2022, 534; Valeriano, Jensen, and Maness Reference Valeriano, Jensen and Maness2018, 36–41).

Using Stuxnet as a case, I define cyberwar as destructive cyberoperations conducted by a nation “against its adversary nation’s critical military or civilian cyber networks and systems with an aim of coercing adversaries and extracting political concessions by inflicting physical damage on these computers, computer systems, and networks,” with such damage possibly, but not necessarily, including injury and death, or total destruction (Akdağ Reference Akdağ2019, 228–29). Cyberwar is exclusively a type of state-to-state cyberconflict because only states possess the capabilities to conduct such operations. It is nonkinetic, but can cause physical destruction to yield concessions from the enemy or to “assert status in international relationships and to teach lessons to other countries” via coercion (Libicki Reference Libicki2009, 121; see also Liff Reference Liff2012, 404–8). Therefore, cyberwar is politically motivated cyberbellicosity, as exemplified by Stuxnet, which may have been employed to maintain the balance of power in the Middle East by disrupting the Iranian nuclear program (Akdağ Reference Akdağ2017, 114–15).

However, conceptualizing cyberwar has prompted great debates among scholars, particularly over whether the incentives for cyberoffensive strategies outweigh those for defensive ones (Gartzke and Lindsay Reference Gartzke and Lindsay2015; Saltzman Reference Saltzman2013; Slayton Reference Slayton2017).Footnote ⁶ The discussion about the offense-defense balance in cyberspace is intellectually rooted in DR’s offense-defense theory, which explains why pro-status quo states engage in war. The theory postulates that military technology geared toward offensive action makes it easier to attack than defend, increasing the odds of war. Structural modifiers (e.g., the mobility of military technology and proximity of targets) can affect the offense-defense balance. The closer the enemy is and the more mobile the offensive technology, the more incentives there are to attack (Jervis Reference Jervis1978; Van Evera Reference Van Evera1998).

Some scholars who have applied offense-defense theory to cyberspace argue that cyberconflict offers more incentives for offense than for defense (Gartzke and Lindsay Reference Gartzke and Lindsay2015, 316). They do so for four reasons. First, acquiring and employing offensive cybercapabilities is easy and cost effective compared to conventional weapons. Second, cyberspace provides a target-rich environment where everything online is vulnerable to attack. Third, conventional aggression mitigators (e.g., territorial distance) are absent in cyberspace. In this sphere, offensive actions have an instantaneous impact, which grants the first mover strategic advantage (Slayton Reference Slayton2017, 77–81; Wilner Reference Wilner2020, 254). Lastly, cyberspace offers anonymity to aggressors, further incentivizing attack over defense.

Other scholars contest this view. They maintain that offensive cyberoperations are neither cheap nor easy to deploy. Stuxnet, for example, took several years to develop and execute due to its complexity, and cost hundreds of millions of dollars (Valeriano and Maness Reference Valeriano, Maness, Brown and Eckersley2017, 266). Erik Gartzke and Jon Lindsay (Reference Lindsay2015) argue that deception strategies (e.g., honeypots) are more advantageous than offensive strategies in cyberspace. Critics challenge the effectiveness of cyberweapons, as they are not capable of disarming an adversary, negating the so-called first-mover advantage of cyberoffense (Slayton Reference Slayton2017, 78–80). While analyzing the offense-defense balance in cyberspace remains an empirical challenge, the perceived dominance of offense appears to be commonplace in great power cybersecurity relations, as substantiated in the 2018 US National Cyber Strategy (Gartzke and Lindsay Reference Gartzke and Lindsay2015, 338–340; The White House 2018).

Although cyberconflict seems to favor offensive strategies, it does not fully correspond to OR’s assumptions. For example, the nonterritoriality of cyberspace brings actors into continuous contact with one another, which complicates the geopolitical calculations that states make. Therefore, I assess the empirical relevance of OR by testing if its assumption about hegemonic expansion applies to cyberspace, and offer conceptual amendments that adapt OR to the realities of this sphere. I begin by comparing OR with DR, clarifying the distinctions in their understandings of the conditions for conflict and peace in the international cybersystem.

Offensive and Defensive Realism

Offensive realism and defensive realism are different branches of structural realism, but they share core assumptions about the ontology of international politics. Both explain systemic outcomes (e.g., war) and state behaviors (e.g., American grand strategy), describe the political structure of international system as anarchic, and consider this anarchy to be the main driver of international conflict (Taliaferro Reference Taliaferro2001, 132–40; Waltz Reference Waltz1979). This anarchical structure is infused with uncertainty because states, as primary and rational actors, distrust the intentions of other states and fear their offensive capabilities. Consequently, states are incentivized by the structure to take self-help measures to increase their relative power and security for survival (Mearsheimer Reference Mearsheimer2001a, 30–32).

Notwithstanding their ontological overlap, OR and DR differ in their understandings of how anarchy influences state behavior, leading to distinct conclusions and policy prescriptions. Kenneth Waltz’s (Reference Waltz1979, 126) DR attributes international conflict to unrelenting competition between states, which seek security but misinterpret the same security-seeking behavior by peers as threatening, resulting in an unresolved paradox of interstate relations: the security dilemma (Jervis Reference Jervis1978). DR defines states as security seekers concerned with maintaining the status quo via balancing, a default security strategy to deter and fight belligerent states. DR’s bias toward the status quo stems from its presumption that aggressive attempts to accumulate power are self-defeating, since they will provoke countervailing attempts by other status quo seekers (Mearsheimer Reference Mearsheimer2001a, 209–11; Snyder Reference Snyder2002, 151–52; Waltz Reference Waltz1979, 126). Thus, Waltz deems a balancing countermove to be an effective deterrent mechanism against aggression (Ripsman, Taliaferro, and Lobell Reference Ripsman, Taliaferro and Lobell2016, 38; Toft Reference Toft2005, 385; Walt Reference Walt1985, 13–14).

In contrast, John Mearsheimer’s OR explains interstate conflict as a phenomenon driven by fierce competition between power-maximizing expansionist states. Mearsheimer (Reference Mearsheimer2001a, 21–36) believes that anarchy causes great powers to be aggressive, revisionist, or expansionist, because it gives them incentives to increase their security by accumulating power, using offensive strategies whenever possible. Importantly, Mearsheimer disputes that balancing is an effective conflict prevention mechanism because states cannot be certain about the right amount of power needed to preserve the existing balance of power, and because balancing is undermined by collective-action pathologies (e.g., free riding) (34–35; Brooks and Wohlforth Reference Brooks and Wohlforth2008, 35–36). Consequently, he contends that major states seek to balance only in rare circumstances. The case in point is Mearsheimer’s “poster child America” (Layne Reference Layne2002, 120), which joined World War II only after the Pearl Harbor raid, when the threat posed by Japan proved to be existential (Mearsheimer Reference Mearsheimer2001a, 181).

Given the challenges to the strategy of balancing, Mearsheimer proposes “regional hegemony” for great powers to effectively prevent and deter aggression and ensure security and survival (Mearsheimer Reference Mearsheimer2001a, 140–44). He conceptualizes a hegemon as the most powerful nation in a region, with a capacity to exert control or influence over the actions of others. The source of hegemonic power is mainly unrivaled military, economic, and political capabilities, or a combination thereof. Accordingly, a state becomes a hegemon when it is “the only great power in the system,” enabling it to dominate that system. Mearsheimer’s understanding of hegemony is then equated with overwhelming material capabilities and their use for coercive purposes (40–41).

Crucially, Mearsheimer (Reference Mearsheimer2001a, 40–42) opposes global hegemony because natural constraints like oceans prevent extraregional power projection. Japan in East Asia and the US in North America exemplify regional hegemons that ensure security in their hinterlands by concentrating power locally, instead of making expensive extraregional commitments (Kirshner Reference Kirshner2012, 60–61).Footnote ⁷ OR’s thesis about regional hegemony informs its vision for great powers: the aim of power-seeking states is ultimately to achieve regional hegemony using offensive strategies under appropriate strategic circumstances. Only after achieving hegemony can major powers guarantee their survival and transform from power maximizers into status quo seekers or reluctant hegemons. In doing so they deter aggression, because rational states avoid conflict with stronger rivals due to the greater chance of defeat (Layne Reference Layne2006, 17–26; Mearsheimer Reference Mearsheimer2001a, 37–43, 169–219; Reference Mearsheimer2001b, 46).

Table 1 outlines the defining features of Mearsheimer’s theory of hegemony and his controversial prediction for the US. His theory predicts that the US would be a reluctant hegemon once it has secured a preponderance of regional power, after which it would stop expanding and become a status quo power, seeking to prevent and deter counterhegemonic aspirations outside its hegemonic sphere of influence by adopting buck-passing or offshore-balancing strategies (Layne Reference Layne2006, 17–26).

Table 1

Offensive Realism’s View of Hegemons and Hegemony

However, I argue that the same balance-of-power mechanism may not apply to state-to-state cybersecurity strategies. Thus, prior to testing OR’s assumption, its view of “hegemony” needs conceptual refinement because cyberspace is incompatible with our traditional understanding of concepts such as war (Rid Reference Rid2012).

Reconceptualizing Hegemony

As discussed above, OR associates hegemony with overwhelming material capabilities and the ability and desire to project them. Because the US exhibits these features in the kinetic world, it qualifies as a hegemon in this sphere. Such a power-centric premise applies to cyberspace too, as cyberhegemons can be characterized by their unrivaled cyberwarfare capabilities and their use of these capabilities for coercive purposes. To accommodate the intricacies of cyberspace, however, it is necessary to modify OR’s framework regarding hegemonic expansion and the level of security OR assumes a hegemon enjoys.

The first such modification concerns OR’s preference for regional rather than global hegemony. For Mearsheimer (Reference Mearsheimer2001a, 32–42), interstate competition causes actors to aggressively pursue regional hegemony to secure their own survival. Regional hegemony is more attainable, as it entails controlling a specific region via superior power, fulfilling the imperatives of a self-help system that stresses security and sovereignty over cooperation. Conversely, Mearsheimer considers the pursuit of global hegemony to be self-defeating because it risks overstretching resources and making costly commitments that no state can afford. This is particularly due to natural barriers that render extraregional power projection unfeasible, and which have caused the demise of great powers that have overlooked this fact (e.g., Napoleonic France).

However, Mearsheimer’s preference for regional hegemony is based on premises that do not apply to cyberspace, a domain whose unbounded, decentralized, and interconnected characteristics remove geographical barriers and create continuous contact among actors. This minimizes the constraining effects of geopolitics on expansionist states, making global power projection practical, cost effective, and often instantaneous (Healey Reference Healey2019, 1; Rid Reference Rid2012, 8). In cyberspace, great powers do not have to make expensive commitments, mobilize extensive resources such as tanks and soldiers, or cross vast oceans or harsh topographies to engage in conflict; global interconnectivity ensures that the enemy is just one click away, eliminating the risk of self-depletion. Consequently, major states are structurally incentivized to pursue global, not regional, cyberhegemony via offensive, expansionist cyberstrategies. Given the relative feasibility of cyberpower projection, a cyber version of OR suggests that big powers would be better off seeking global cyberhegemony to achieve deterrence and security in cyberspace. This adjustment to the concept of hegemonic expansion in cyberspace will be tested using the US as a case study.

The second modification addresses the degree of security that OR assumes regional hegemons enjoy. Mearsheimer (Reference Mearsheimer2001a, 34–42) expects the US, as a regional hegemon, to transform from a power-seeking, expansionist state into a reluctant hegemon that seeks to preserve the status quo, secured by its formidable material capabilities and by natural barriers that isolate it from major competitors. To maintain this power position, OR predicts that the US will deter bids in distant regions to counter its hegemony via buck-passing or offshore-balancing strategies (Layne Reference Layne2006, 17–26). However, cyberconflict challenges OR’s notion of a secure and reluctant regional hegemon for two interconnected reasons.

First, the US is less secure in cyberspace, as the nonterritoriality of cyberspace invalidates the defensive advantages its geographical location provides. Second, while internet connectivity augments American hegemonic power, it also leaves the US more susceptible to cyberthreats than less-wired states (Kesan and Hayes Reference Kesan and Hayes2012, 443). Former president Barack Obama (Reference Obama2009) underlined this paradoxical situation: “It’s the great irony of our Information Age—the very technologies that empower us to create and to build also empower those who would disrupt and destroy. And this paradox—seen and unseen—is something that we experience every day.” Obama’s last sentence also reflects the clandestine nature of cyberthreats, as system and network intrusions may go undetected. For example, US House representative Michael McCaul suspected China of deploying logic bombs—malicious code that lies dormant until needed—in American infrastructure to use in times of conflict. This insecurity underlies the Assumed Breach paradigm governing cybersecurity discourse (Lindsay Reference Lindsay2015, 7).

The White House’s 2018 National Cyber Strategy also recognizes the vulnerability of critical US infrastructure to cyberattacks (The White House 2018, 2–3). This uncertainty, coupled with its high degree of internet connectivity, makes the US a relatively insecure and more vulnerable hegemon in cyberspace. To deter cyberthreats and achieve cybersecurity, then, Washington can be expected to pursue global cyberhegemony through constant expansion and cyberpower maximization, and not seek to preserve the status quo as a reluctant regional hegemon.

Table 2 demonstrates how the modified version of OR conforms to the realities of cyberspace. Based on table 2, I define global cyberhegemony as a power position in which a state is perceived to possess overwhelming offensive and defensive cybercapabilities, and seeks to project its cyberpower globally to achieve security and deterrence in cyberspace. Can the US dominate cyberspace via cyberhegemony? Cyberdominance means that a state has the ability to achieve and maintain a superior position from which it can effectively disrupt, destroy, control, and influence others’ cyberactions. Empirical data suggest that the US’s cybersecurity paradigm is relatively effective, as Washington has achieved escalation dominance by extracting the most concessions from its cybercompetitors, including China, using offensive cyberstrategies (Valeriano, Jensen, and Maness Reference Valeriano, Jensen and Maness2018, 82).Footnote ⁸ To achieve and maintain global cyberhegemony, the US can concentrate on upgrading its digital infrastructure via research and development, artificial intelligence, and quantum computing. Although technological leadership could theoretically secure cyberdominance for Washington, it remains to be seen whether the US can achieve such dominance given the fluidity of cybertechnology.

Table 2

Comparative Analysis of Offensive Realism’s Views on Hegemony

However, not all states can afford to pursue global cyberhegemony. Cyberspace offers easy access to the playing field, but cyberpower is not cheap to acquire. There may be significant temporal, organizational, and resource constraints to pursuing a preponderance of cyberpower. For instance, Stuxnet took years to develop, cost over $300 million, and required the cooperation of two countries. Therefore, while producing cyberpower is cost effective relative to conventional and nuclear power, it still carries considerable costs that not all cyberactors can afford (Slayton Reference Slayton2017, 84–90; Valeriano, Jensen, and Maness Reference Valeriano, Jensen and Maness2018, 36–41).

Defensive Realism as an Alternative Explanation

As previously noted, Waltz’s DR treats expansionism and aggression in world politics as counterproductive due to the prospect of balancing countermoves against potential hegemons (e.g., the alliances against Germany in World War I and World War II) (Rendall Reference Rendall2006, 523–24). For DR, therefore, stability rests on an interstate power equilibrium. Based on this balance-of-power perspective, DR argues that the US will avoid pursuing global cyberhegemony even in the absence of strategic restraints on the expansion of its cyberpower, as Washington would likely encounter an antihegemonic cyberalliance that would defeat its security-seeking purpose. This situates DR as an alternative framework to OR in explaining how states seek security and power in cyberspace—whether via expansion or via the balance of power.

However, I argue that DR’s framework has poor explanatory power in cyberspace. A counterhegemonic balancing strategy is unlikely to serve as a structural limitation on expansion in cyberspace because the nature of cyberpower and cyberconflict exacerbates the difficulties involved in achieving a balance. These balancing problems—including those unique to cyberspace—pose considerable risks and challenges to states, reducing the likelihood of effective countermoves. I identify four such problems below.

First, the opaque nature of cyberpower may make it harder for states to judge the cybercapabilities of other states, complicating attempts to balance against cyberthreats. Mearsheimer (Reference Mearsheimer2001a, 2–21) raises this crucial point when he expresses skepticism about the prospects of forging a successful counterhegemonic coalition—a strategy undermined by the impracticality of assessing whether coalition partners have the right amount of power needed to achieve equilibrium and by other balancing flaws (Sheldon Reference Sheldon2011, 100). This uncertainty is even greater in cyberspace as shifts in the interstate balance of cyberpower can occur faster due to the adaptability and volatility of cybertechnology.

The Belfer Center’s National Cyber Power Index (Voo et al. Reference Voo, Hemani, Jones, DeSombre, Cassidy and Schwarzenbach2020; Voo, Hemani, and Cassidy Reference Voo, Hemani and Cassidy2022) underlines the fluidity of interstate cybercapabilities. The index’s comparative analysis shows that Russia’s cybercapabilities overtook those of the United Kingdom within just two years—a rapid shift compared to conventional power transitions (consider the decades taken by China to catch up with the US economically) (Voo, Hemani, and Cassidy Reference Voo, Hemani and Cassidy2022, 10–12). This volatility creates extra uncertainty, increasing cyberthreat perceptions among great powers such that they assume worst-case scenarios. This in turn drives them to maximize their cyberpower via expansionist strategies, and ultimately to seek global cyberhegemony to preserve their cybersecurity and deter potential cyberthreats. Such dynamics undermine cyberstrategies based on the balance of power, which has implications for CPT’s core concepts and assumptions, as I will discuss below.

Second, counterhegemonic balancing may fail in cyberspace because cyberalliances risk entangling great powers in the conflicts of other states. Small states may draw larger alliance members into war by provoking major cyberadversaries, just as the conflict between Austria and Serbia in World War I evolved into a war between Austria, Germany, Serbia, and Russia. Hypothetically, a small state conducting punitive cyberstrikes against China could trigger a kinetic retaliation; and if the state were a member of NATO, the organization’s Article 5 provisions could draw the US into a major conflict and/or cyberwar with China, undermining collective attempts to balance against common cyberthreats and incentivizing cyberpower maximization and expansion for cybersecurity (Libicki Reference Libicki, Minárik, Alatalu, Biondi, Signoretti, Tolga and Visky2019, 10–11). Correspondingly, the cybersecurity of a member of a counterhegemonic cyberalliance is integral to the security of the rest due to the interconnectedness of cybersystems. To illustrate, if the Five Eyes alliance became a cybersecurity coalition, the US could be dragged into a cyberwar with China when an alliance member faced a cyberthreat from Beijing. Neutrality would be unlikely to be an optimal option given the coalition’s cybersecurity interdependence, rendering balancing against hegemonic cyberpowers a risky strategy and diminishing the efficiency of Waltz’s balance of power.

Finally, the nature of cyberconflict may negate the benefits of coming together for collective defense and deterrence. A negative correlation exists between the size of a cyberalliance and its effectiveness, as adding members amplifies vulnerabilities that can be exploited, deepens the challenges involved in defending the alliance’s systems, and potentially decreases the quality of the alliance’s cybercapabilities due to differences in training levels. The volatility of cybertechnology (e.g., the loss of a cyberweapon’s effectiveness once it is exposed) can also discourage states from sharing cybercapabilities against a common cyberthreat. Additionally, counterhegemonic cyberbalancing may be undermined by the mistrust that lingers even within cyberalliances, since states spy on each other in cyberspace, as evidenced by the Snowden revelations (DeVore and Lee Reference DeVore and Lee2017, 45; Libicki Reference Libicki, Minárik, Alatalu, Biondi, Signoretti, Tolga and Visky2019, 3–11).

To recap, counterhegemonic cyberbalancing as a security mechanism is unlikely against expansionist great powers due to the characteristics of cyberpower and to difficulties in achieving a balance. This offers structural incentives for states to maximize their own cyberpower—rather than balance against that of others—as the costs of expansion are not prohibitive in cyberspace. The empirical assessments made in the next section reinforce this conclusion.

Because the dynamics of the balance of power do not operate in cyberspace and counterhegemonic balancing is unlikely, there are no structural barriers preventing major states from seeking global cyberhegemony. As such, the dominant behavior in cyberspace becomes one of expansion and power maximization for cybersecurity given the minimal risks and costs involved. Major states, including the US, risk undermining their cybersecurity if they do not constantly pursue power and advantage as incentivized by the structure of cyberspace. Within the boundless and unsecured domain of cyberspace, opportunities that are not seized are ceded to adversaries, risking national security both within and through cyberspace.Footnote ⁹

OR’s analytical value and its theoretical relevance to cyberspace is not entirely contingent on the modified concept of hegemony outlined above. Mearsheimer’s core assumptions remain valid in cyberspace, as secrecy, uncertainty, mistrust, and the perceived advantage of offense dominate cyberengagements (Mearsheimer Reference Mearsheimer2001a, 31–32). Uncertainties about relative cybercapabilities and intentions shape states’ policies toward other cyberactors (e.g., strategic cyberdeterrence) (Valeriano, Jensen, and Maness Reference Valeriano, Jensen and Maness2018, 41). Scholarship acknowledges the anarchical characteristics of cyberspace, which lacks conflict prevention tools (such as interstate cooperation), well-established cyber-specific laws, and a global system of governance.Footnote ¹⁰ Consequently, mutual fear and cyberinsecurity guide the actions of states in this sphere, causing cyber arms races and eventually cyberconflict. For example, Craig and Valeriano (Reference Craig, Valeriano, Pissanidis, Rõigas and Veenendaal2016, 146–51) find that both Iran and the US build cyberarms due to feelings of mutual fear and cyberinsecurity, which have been exacerbated after Stuxnet. While the extent to which cyberspace can be defined as anarchical is disputable, OR appears well equipped to explain how the dynamics of cyberanarchy affect state-to-state cybersecurity interactions.Footnote ¹¹

Testing Offensive Realism’s Assumption of Hegemonic Expansion in Cyberspace

This study aims to examine whether OR’s theoretical and conceptual tools offer a plausible and empirically relevant understanding of interstate security relations in cyberspace. I qualitatively evaluate whether OR’s thesis about hegemonic expansion holds in the virtual domain using the US as a case study. Mearsheimer (Reference Mearsheimer2001a, 140–46) contends that great powers exercise influence and power only within their region, as doing so across topographical barriers entails costly economic and military commitments that impose strategic restraints on extraregional power projection. Mearsheimer therefore favors regional but not global hegemony to avoid self-depletion, implying that without such barriers, great powers would pursue global hegemony. If he is correct, the US should seek to expand its cyberpower and influence globally due to the absence of these constraints in cyberspace.

To examine whether Washington has been seeking global cyberhegemony, I analyze the US’s major declaratory cyberpolicies and cyberstrategies from 2003 to 2023, as well as the Stuxnet and Snowden incidents. This analysis seeks to establish whether the US has intended to expand its cyberpower and influence beyond its hinterland by adopting offensive cyberstrategies. Exercising power and influence in cyberspace can take many forms. Washington’s cyberdiplomacy with countries outside its region indicates its commitment to expanding its global reach; the US’s attempts to establish international cyber-specific norms and promote American ideological values (e.g., the free flow of information) signifies an interest in shaping the global governance of cyberspace; and the worldwide operations of US-based ICT corporations (e.g., Google) and the cyberinterventions of the US Department of Defense (DoD) across multiple regions reflect the US’s ambition to maintain influence, control, and power beyond its back yard.Footnote ¹²

Examining the Stuxnet and Snowden cases serves two purposes: to underline Washington’s offensive cybercapabilities and its intention to shape events and outcomes in the international cyberecosystem, and to demonstrate whether the US’s behavior in cyberspace conforms to its cybersecurity doctrines. Before moving on to these cases, I first examine the US’s major declaratory cybersecurity policies to establish whether it has clearly articulated hegemonic ambitions in cyberspace.

Analyzing Major US Cybersecurity Policies (2003–23)

The Bush administration’s National Strategy to Secure Cyberspace, launched in 2003, represents a significant milestone in the evolution of the US cybersecurity paradigm. Although it has multiple purposes, its primary function is to advise US leaders on how to address global cybersecurity issues via international cooperation: “America must be ready to lead global efforts, working with governments and industry alike, to secure cyberspace that is vital to the operation of the world’s economy and markets” (The White House 2003, 49). This signifies the US’s intent to create global cybersecurity standards and expand its influence in cyberspace.

However, despite suggesting greater American hegemonic leadership in cyberspace, the document avoids overtly endorsing aggressive US expansion in this domain at the expense of its rivals. Instead, it highlights defensive and denial measures for safeguarding national cyberinfrastructure, makes vague references to interstate punitive cyberstrategies, and calls for the prosecution only of transnational cybercrimes (The White House 2003, 49–40; Wilner Reference Wilner2020, 257). Anticipating potential blowbacks against innocent parties made vulnerable by global interconnectivity, the Bush administration deemphasized aggressive cyberstrategies (Wilson Reference Wilson2004, 10). Thus, the US’s cybersecurity paradigm favored defense over offense during the 1990s and early 2000s.

However, offensive cyberstrategies in the US’s cybersecurity thinking began to rise to prominence during the Obama administration. A key indicator of this was the creation of US Cyber Command (USCYBERCOM) in 2010. Initially commissioned with protecting US government’s cybersystems and cybernetworks, USCYBERCOM would later expand to develop offensive cybercapabilities and conduct offensive cyberoperations (US Department of Defense 2018; Wilner Reference Wilner2020, 259–61).

In 2011, the White House and DoD broadened the country’s cybersecurity doctrine with the “Strategy for Operating in Cyberspace.” It identifies five strategic initiatives, including treating cyberspace “as an operational domain” and working with allies to reinforce “collective cybersecurity” via cyberdeterrence (US Department of Defense 2011, 1–9). While USCYBERCOM constituted the DoD’s main conduit for offensive cyberstrategies, the 2011 document did not clearly link the US’s cyberdeterrence posture to aggressive cyberstrategies but rather prioritized defense and denial measures and related lexicon (e.g., restrain and resilience).

Correspondingly, the DoD’s 2011 doctrine did not embrace ambitious, aggressive cyberstrategies to expand American influence abroad, but rather highlighted cybernorms, collective self-defense with allies (e.g., enhancing “warning capabilities”), and the security of cyberspace: “DoD will assist US efforts to advance the development and promotion of international cyberspace norms and principles that promote openness, interoperability, security, and reliability” (US Department of Defense 2011, 9–10). Yet in the 2013 Task Force Report, the DoD suggested a gradual strategic shift from defense to offensive cybercapabilities and nuclear deterrence to protect vital interests and deter bellicose cyberactors via punishment (Wilner Reference Wilner2020, 261–62).

In the 2015 DoD Cyber Strategy, the strategic language still favored a “doctrine of restraint” but signaled a shift toward offensive cyberoperations, including retaliatory strikes against adversaries. In previous documents, the DoD had underlined defensive (e.g., firewall) and denial (e.g., resilience) cybercapabilities to counter cyberthreats, but the 2015 strategy indicated Washington’s intent to confront cyberattacks against American interests “at a time, in a manner, and in a place of our choosing, using appropriate instruments of US power” (US Department of Defense 2015, 11). It outlined offensive tasks for USCYBERCOM as well as DoD plans to incorporate offensive cybercapabilities into military operations. The document highlighted the strategic significance of the Cyber Mission Force, which was created between 2012 and 2013 to counter cyberthreats and defend American interests in cyberspace. The 2015 strategy stated that the Cyber Mission Force would have a personnel of over six thousand once fully operational, aligning with its goal of building and maintaining US mission capabilities in cyberspace (US Department of Defense 2015, 6–11; Wilner Reference Wilner2020, 262–65).

The DoD’s shift toward developing more offensive capabilities was driven by the strategic context of the time. The 2015 document identified Russia and China as dangerous competitors developing sophisticated cybercapabilities to undermine US interests (US Department of Defense 2015, 6–11). To address this, the 2015 strategy reiterated the need for US leaders to build cybercapacity with allies and secure critical infrastructure, including military and government networks. But it limited the US’s global involvement in collective cyberdefense and cyberoffense operations to “priority regions” (e.g., Asia-Pacific) that have historically been pivotal to American grand strategy (US Department of Defense 2015, 26–28).

The rise of offense-leaning concepts in US cyberpolicies since the Obama administration has been accompanied by empirical precedents. The discovery of Stuxnet in 2010, Edward Snowden’s revelations in 2013 about the aggressive use of National Security Agency (NSA) cybercapabilities, and American cyber-retaliation against North Korea for its cyberattacks against Sony Pictures in 2014 are prominent cases (Mazzetti and Schmidt Reference Mazzetti and Schmidt2013; Wilner Reference Wilner2020, 263–64).

These examples demonstrate a mismatch between the US’s declared policy of operational “restraint” and its cyberpractices between 2010 and 2014. During these years, USCYBERCOM aggressively used its capabilities to disrupt and destroy the cybersystems of both adversaries and allies, as the Snowden revelations and Stuxnet made clear. These practices indicate that the US did not in fact adhere to the “doctrine of restraint” or largely allow adversaries’ cyberbellicosity to go unpunished in the 2010–14 period, contrary to the findings of CPT analysis of US cyberpolicy during the same years (Fischerkeller, Goldman, and Harknett Reference Fischerkeller, Goldman and Harknett2022, 131–32).

Yet the US’s 2018 cyberpolicies conspicuously prioritized offensive cyberstrategies, such as preemptive cyberattacks, to slow the rise of challengers and expand American influence globally. Such a dramatic shift reflected a recognition that the traditional deterrence paradigm (and its doctrine of restraint) in American strategic cyberthinking was limiting the US’s ability to further its national interests in cyberspace. This view was reinforced by the DoD’s anticipation of prolonged strategic cybercompetition with China and Russia, two adversaries that have persistently sought to undermine the power of the US and its allies. To maintain the US’s military overmatch and safeguard American interests, the DoD adopted two strategies combining offense and defense: “persistent engagement” and “defend forward.” These strategies aimed to proactively engage with and disrupt malicious cyberactivities at their source, persistently counter cyberthreats, and degrade adversaries’ capabilities and networks (Fischerkeller, Goldman, and Harknett Reference Fischerkeller, Goldman and Harknett2022, 128–40; US Cyber Command 2022; US Department of Defense 2018, 2–4).

Within the “persistent engagement” framework, USCYBERCOM leads efforts to execute cybermissions and achieve and maintain American superiority in cyberspace. At the Department of Homeland Security’s 2018 Cybersecurity Summit, Vice President Mike Pence (Reference Pence2018) confirmed that the US’s intention was to achieve cyberhegemony: “Our goal remains: American security will be as dominant in the digital world as we are in the physical world.”

As the first fully articulated national cyberpolicy, the Trump administration’s US National Cyber Strategy, launched in 2018, complements USCYBERCOM’s vision. It tasks cyberwarriors with maintaining peace and cybersecurity via “strength,” cyberpower preponderance, and cooperation with US allies. The policy stresses Washington’s primary goal: to “[i]dentify, counter, disrupt, degrade, and deter” cyberactivities that jeopardize US national interests while maintaining cyberdominance (The White House 2018, 20–26). Consistent with this hawkish posture, it threatens to impose “swift and transparent consequences” on those who challenge American interests in cyberspace (The White House 2018, 21).

Furthermore, the document champions the expansion of US global influence and encourages the country to “launch an international Cyber Deterrence Initiative” with allies to punish cyberbellicosity and deliver a deterrent message to adversaries. It also seeks to uphold the US-held values of “an open, interoperable, reliable, and secure Internet” as well as the multistakeholder model in cyberspace, reaffirming the country’s commitment to expanding its extraregional influence (The White House 2018, 20–24).

The Biden administration’s National Cybersecurity Strategy, launched in 2023, largely represented continuity with the ambitious and aggressive posture of 2018 that embraced global US cyberhegemony. The document advocates maintaining US superiority in cybertechnology and innovation. It reaffirms the US’s commitment to working with allies to build collective cybersecurity, establish cybernorms, punish violations, and protect US-held values (e.g., individual liberty) against “the dark vision for the future of the Internet” advocated by autocratic regimes such as China (The White House 2023, 29). The strategy addresses steps to expand the US’s influence and leadership, such as the 2022 Declaration for the Future of the Internet (US Department of State 2022), to maintain and reinforce the US-sponsored internet governance regime.

However, the Biden administration changed the nature of American assistance to countries under cyberattack, such as Ukraine (The White House 2023, 2–7). The US extended its help beyond defensive efforts to include offensive measures against cyberaggressors, clearly demonstrating its interest in acting as a global cybersecurity provider through an offense-based strategy (The White House 2023, 28–31). In parallel, the Biden administration demanded an updated “defend forward” approach. Consequently, the DoD published a two-page summary of its 2023 cyberstrategy and pledged to “maximize its cyber capabilities” for “integrated deterrence.” It reaffirmed “hunt forward” cybermissions “to disrupt and degrade” adversaries’ capabilities and reiterated a desire to collaborate with allies to increase cybercapacity and safeguard cyberspace, signaling the US’s intention to dominate interstate cybersecurity competition via offensive strategies (US Department of Defense 2023).

The US’s major cyberpolicies from 2003 to 2023 demonstrate that Washington has been seeking extraterritorial expansion of its cyberpower and influence. It aims to achieve global cyberhegemony primarily by exercising offensive cybercapabilities to maximize its cyberpower, deter cyberadversaries, and ensure its cybersecurity. Especially since the Obama administration, Washington has grown more ambitious, expansionist, and hawkish in its external cyber-relations. It has done so in three ways. First, the US has sought to expand its global reach and hegemonic leadership in cyberspace, primarily through a preponderance of cyberpower and secondarily through internet governance, collective cybersecurity, and technological supremacy. Second, US cyberpolicies emphasize the US’s determination to undermine revisionist states (e.g., China) via offensive cyberstrategies (e.g., preemptive strikes). Third, and relatedly, Washington has espoused increasingly ambitious, expansionist, and aggressive cyberstrategies (e.g., “defend forward”) that seek to exploit adversaries’ cybervulnerabilities to alter or maintain the balance of cyberpower in its favor. In the following sections, I examine Stuxnet and the Snowden revelations to showcase the power and global extent of the US’s cybercapabilities.

Stuxnet

The case of Stuxnet is important for several reasons. First, it exemplifies Washington’s interest in extraregional cyberpower projection and its bid for global cyberhegemony using offensive cyberstrategies. Second, Stuxnet shows that the US’s cyberbehaviors are consistent with its hawkish cybersecurity policies. Third, Stuxnet demonstrates the superiority of the US’s cyberwarfare capabilities over those of other countries, a sign of hegemonic power. Fourth, it details the nature of hegemonic cyberconflict.

Stuxnet epitomizes Washington’s willingness to exercise cyberpower to achieve global outcomes. Uncovered in 2010, Stuxnet was developed under the Bush administration in 2006 as a part of Operation Olympic Games, a program to target the Iranian nuclear facility at Natanz without a kinetic attack. Initially, the NSA and the Central Intelligence Agency (CIA) collected intelligence on the facility’s systems to identify vulnerabilities. American agencies then collaborated with their Israeli counterparts to create a sophisticated and malicious code that exploited these vulnerabilities, which would later come to be known as Stuxnet. Stuxnet’s deployment was authorized by the Bush administration in 2008, but the Obama administration intensified efforts to ensure Stuxnet’s success, demonstrating the US’s long-term strategic shift toward offensive cyberstrategies and extraregional cyberpower projection (Jenkinson Reference Jenkinson2021, 19–24; Sanger Reference Sanger2012, 110–29).

Stuxnet has distinctive characteristics that illustrate Washington’s cyberwarfare capabilities and technological prowess. The first concerns its level of sophistication. Cybersecurity expert Robert McMillan called Stuxnet one of “the most sophisticated and unusual pieces of software ever created” (quoted in Farewell and Rohozinski Reference Farwell and Rohozinski2011, 23). Stuxnet exploited four “zero-day vulnerabilities” (undiscovered loopholes in software) to degrade its target, an accomplishment requiring substantial resources, expertise, and extensive intelligence gathering (Farewell and Rohozinski Reference Farwell and Rohozinski2011, 23–25; Lindsay Reference Lindsay2013, 365–66). Stuxnet gradually changed the rotation velocity of uranium enrichment centrifuges, eventually causing their physical destruction. Its ingenuity also lay in its stealth, as Iranian cyberoperators remained oblivious until it was too late. Moreover, Stuxnet was programed to self-destruct once it had completed its mission (Singer Reference Singer2015, 80–83). Hence, Stuxnet’s sophistication and rigorous deployment process demonstrated the US’s ability and desire to project its cyberpower globally (Jenkinson Reference Jenkinson2021, 19–24; Valeriano, Jensen, and Maness Reference Valeriano, Jensen and Maness2018, 40).

Stuxnet also offers significant insights into the nature of hegemonic cyberconflict. First, it confirmed that such conflict can have tangible effects outside cyberspace. German security consultant Ralph Langner dubbed Stuxnet a “military-grade cyber missile” targeting Iran’s nuclear program (quoted in Farwell and Rohozinski Reference Farwell and Rohozinski2011, 23; Lindsay Reference Lindsay2013, 366). Second, Stuxnet emphasized the strategic, political, and coercive nature of cyberconflict: it aimed to prevent Iran from obtaining nuclear weapons, keep the Middle East’s balance of power weighed in Israel’s favor, and gain political and military advantages over Iran. Third, Stuxnet reflected the coercive aspect of cyberconflict in extracting political concessions. The delay to Iran’s nuclear program caused by Stuxnet and the fear of another crippling cyberattack by the US and Israel might have convinced Tehran to sign the 2015 nuclear deal (Akdağ Reference Akdağ2017, 121–22).Footnote ¹³

Stuxnet has not played a central role in advancing US cyberhegemony, but it does illustrate that the US has the superior cybercapabilities characteristic of a hegemonic power. The fact that no cyberoperations like Stuxnet have come to the public’s attention since 2010 does not necessarily suggest that the US’s cybersecurity paradigm has evolved from coercion to exploitation, as CPT argues (Fischerkeller, Goldman, and Harknett Reference Fischerkeller, Goldman and Harknett2022; Mearsheimer Reference Mearsheimer2001a, 40–44). First, cyberoperations are naturally clandestine; they often remain unexposed for years. Stuxnet was discovered years after it had first been deployed. Thus, it is possible that great powers, including the US, may have conducted numerous destructive cyberoperations that have remained unpublicized or undiscovered (Akdağ Reference Akdağ2023, 18).

Second, while destructive and coercive cyberoperations dramatically risk escalation, the US appears to have managed escalatory cyberdynamics effectively. As cited above, empirical data indicate that when the US has escalated cyberquarrels, its opponents, including China, have chosen to deescalate, and that the US has acquired more concessions from adversaries by using offensive capabilities (Valeriano, Jensen, and Maness Reference Valeriano, Jensen and Maness2018, 82). Therefore it may be erroneous to ascribe the rarity of destructive US cyberoperations merely to a strategic shift toward exploitation. Indeed, CPT theorists admit that their case analysis of the US’s cyberstrategy until 2022 indicates that US behaviors do not entirely align with CPT’s logic of exploitation and initiative persistence: “Although White House and congressional actions tacitly supported an acceptance of this new paradigm, its core strategic principle has not yet been deliberately and evenly adopted across the whole of government” (Fischerkeller, Goldman, and Harknett Reference Fischerkeller, Goldman and Harknett2022, 156). Hence it remains to be seen whether constant expansion or initiative persistence dominates cyberspace, as empirical data emerge over time.

Stuxnet highlights Washington’s use of cyberpower to intervene in the affairs of other counties beyond its own region. This extraregional engagement reflects the US’s bid for global cyberhegemony using offensive cybercapabilities, an interpretation reinforced by the Snowden revelations.

Snowden Revelations

The Snowden revelations capture the extent of US hegemonic ambitions in cyberspace, detailing covert, offensive US cyberoperations that aimed to expand the US sphere of influence by projecting US cyberpower across the world. They offer further indications that Washington seeks global cyberhegemony.

In June 2013, Edward Snowden, a former CIA systems analyst and NSA contractor, revealed classified data on global US surveillance operations to journalists Glenn Greenwald, Ewen MacAskill, Barton Gellman, and Laura Poitras, who subsequently reported on the data in the Guardian, Washington Post, and other publications. The reports indicated that since 2007, the NSA had systematically conducted covert surveillance activities to gather national and international digital data such as phone records (Inkster Reference Inkster2014, 51–54; Landau Reference Landau2013, 54–58; Wahl-Jorgensen, Bennett, and Taylor Reference Wahl-Jorgensen, Bennett and Taylor2017, 1–4).

The NSA’s surveillance was global in scope, targeting countries across Asia, Europe, Latin America, and Africa. The NSA reportedly infiltrated Chinese public and private networks, including those of the government and businesses, to collect intelligence and identify attack vectors. Even the US’s allies and partners were not spared from the NSA’s pervasive spying activities. The agency’s intrusive cyberoperations included eavesdropping on the computerized networks and communications of foreign embassies and members of the European Union (EU), as well as intercepting the phone calls of the EU’s political leaders, including German chancellor Angela Merkel. Reports suggested that the NSA tapped into millions of phone calls in Spain and France and monitored formal and informal communications in friendly Latin American countries such as Chile and Brazil. Turkey, South Africa, Japan, South Korea, and India were also targeted by the NSA’s intrusive and offense-orientated cyberactivities, which included cyberdegradation, cyberespionage, and surveillance (Borger Reference Borger2013; Wahl-Jorgensen, Bennett, and Taylor Reference Wahl-Jorgensen, Bennett and Taylor2017, 5–6).

Snowden’s leaks undoubtedly reveal the US’s ambitions to achieve global cyberhegemony via extraregional cyberpower projection to shape international outputs. The revelations disclosed programs to map the global cyberecosystem for real-time intelligence gathering, such as “Treasure Map;” conduct cyberespionage and intrusive surveillance on Americans, allies, and adversaries; and implant malicious code into the networks of adversaries to execute precision cyberattacks on their command-and-control systems. Additionally, they indicate a conformity between Washington’s behavior in cyberspace and American cybersecurity doctrines that have increasingly favored ambitious, expansionist, and aggressive interstate engagements. Extraregional US cyberinterventions like those revealed by Snowden reflect Washington’s acceptance that it is in strategic competition with adversaries such as China and Russia, and are evidence of its desire to achieve global cyberhegemony through offensive cyberstrategies or hegemonic cyberconflict (Valeriano, Jensen, and Maness Reference Valeriano, Jensen and Maness2018, 171–72).

The US has a rich history of offensive cyberoperations (as illustrated by the Snowden revelations), which demonstrates its willingness to leverage its cybercapabilities for strategic ends. The expansion of USCYBERCOM underscores Washington’s focus on enhancing its offensive and defensive cybercapabilities and on projecting its power through cyberspace. The US works with international partners and helps to build cybercapacity in allied countries for collective cyberdefense and cyberoffense. Such collaboration serves as a means by which the US can expand its global influence in cyberspace. Strategies such as “defend forward” demonstrate the US’s willingness to engage in preemptive actions that neutralize cyberthreats in advance and to operate within adversary networks—offensive postures orientated toward maintaining cyberdominance and preemptively disrupting adversaries. Following a Hobbesian logic, it would be naïve to assume that states would exploit vulnerabilities to seize initiative persistence but not to prepare future attack vectors in case they are needed (Whyte Reference Whyte2018, 529–30). While the 2023 National Cybersecurity Strategy underscored the importance of resilience and defense, it also emphasized the need for offensive measures and for research and development to counter adversaries. The Biden administration’s strategy might frame cyberactions as defensive, but it is inherently expansionist in nature. The strategy extends the US’s cyberoperations across regions, aligning with its goal of pursuing cyberpower and global cyberdominance (The White House 2023).

The case analysis here concludes that great powers seek cyberpower maximization and expansion rather than initiative persistence to enhance their cybersecurity. Although this analysis and CPT cover US cyberstrategy and policy in the same period, the conclusion I reach here contrasts with that made by CPT scholars (Fischerkeller, Goldman, and Harknett Reference Fischerkeller, Goldman and Harknett2022). The distinction arises from how one conceptualizes offensive and defensive actions in cyberspace. A definition of what counts as offensive or defensive cybermeans remains elusive because their characteristics overlap, a function of the fluid nature of cybertechnology. A code can exploit vulnerabilities for offensive and defensive purposes simultaneously: “Moves that are said to be defensive involve forward maneuver that can seem offensive in nature. Offensive operations set to impose costs on the opposition are often thought to be defensive in nature.” For example, “the US rerouting of server traffic for a ransomware group” is both an offensive and a defensive operation (Valeriano Reference Valeriano2022, 95). While it is “proactive” and occurs in the target’s networks, it is also nonviolent and protective of the US’s position in cyberspace.

Indeed, the strategy of persistent engagement is offensive at its core, as it requires aggressive actions such as the preemptive disruption and destruction of the cybersystems of would-be cyberchallengers. Brandon Valeriano’s (Reference Valeriano2022, 94–95) reading of Michael Fischerkeller and Richard Harknett’s CPT signals this dual nature and the offense-dominant aspect of their doctrine: “Fischerkeller and Harknett have advocated for the strategic doctrine of cyber persistence because the enemy is persistent and the only way to counteract an adversary’s offensive cyber actions is to take even earlier offensive action.” However, CPT theorists consider cyberactions that seek initiative persistence for security and strategic gains to be inherently exploitative. CPT’s analysis consequently reaches a different conclusion from that of modified OR (Fischerkeller, Goldman, and Harknett Reference Fischerkeller, Goldman and Harknett2022, 52).

Conclusion and Implications

Mearsheimer’s theory of offensive realism argues that regional, rather than global, hegemony best serves the goal of ensuring security for great powers because natural obstacles render global power projection costly and extraregional hegemonic commitments self-depleting. Mearsheimer implies that without such hurdles, the lower cost of extraregional power projection would prompt great powers to pursue global hegemony. Using the US as a case study, I tested this assumption about hegemonic expansion in cyberspace, as the borderless nature of the domain removes strategic restraints on global expansion. If OR’s prediction is accurate, one would expect the US to pursue global cyberhegemony, using offensive cyberstrategies to deter rival powers and ensure its cybersecurity.

I argued that OR has meaningful inferential and predictive power in cyberspace, and confirmed its empirical relevance and analytical ability to explain interstate cybersecurity engagements, specifically cyberdeterrence interactions in hegemonic cyberconflicts. My empirical assessment of the US’s cyberpolicies between 2003 and 2023, the Stuxnet incident, and the Snowden revelations corroborates OR’s assumption that hegemons will seek to expand their power beyond their own regions in cyberspace. Washington pursues global cyberhegemony with an ambitious, expansionist, and cyberpower-maximizing approach to interstate cyber-relations. It engages in agreed competition that falls short of war, particularly with China, to increase its strategic gains while preventing its adversaries from doing the same, to deter malicious cyberactors, and to ensure its cybersecurity through a preponderance of cyberpower (Fischerkeller and Harknett Reference Fischerkeller and Harknett2019).

This conclusion has significant theoretical and policy implications. First, OR’s empirical relevance in cyberspace may address skepticism about whether realism is applicable to this domain. Second, the empirical analysis substantiates modified OR’s conceptual framework for hegemony that I proposed in table 2. The US pursues global—not regional—hegemony in cyberspace, as the domain presents new conditions, imperatives, opportunities, constraints, and capabilities that incentivize the pursuit of global dominance and challenge DR’s counterbalancing thesis (Choucri and Clark Reference Choucri and Clark2018, 351). My findings substituted Mearsheimer’s regional, secured, reluctant, and status quo-seeking hegemon with a global, insecure, ambitious, and expansionist cyberhegemon. Security is scarce for the US in cyberspace because the domain’s boundless characteristics nullify the defensive advantages that the US enjoys in conventional space. The US also faces greater vulnerabilities due to its disproportionately high reliance on the internet relative to less-wired nations like China, rendering it a relatively insecure and more vulnerable hegemon. To reduce its cyberinsecurity and deter cyberthreats, Washington pursues global cyberhegemony by seeking to maximize the degree and reach of its cyberpower, and by preventing its adversaries from making strategic gains and enhancing their own cybersecurity.

Third, the analysis has policy implications for the DoD’s 2018 and 2023 cyberdoctrines, including “persistent engagement,” “defend forward,” and “agreed competition,” which have provoked debates among scholars and policy makers (Klimburg Reference Klimburg2020, 107). Some academics argue that cyberdeterrence lacks credibility as a conflict prevention mechanism, and instead propose that the US would be better able to deter cyberadversaries and secure its cybersystems by proactively engaging malicious cyberactors. This proactive engagement requires using cybercapabilities aggressively, such as by neutralizing potential cyberthreats at their origin (“defending forward”). Although it appears escalatory, this strategy could stabilize cyberconflict if actors comply with the norms and rules of agreed competition (Fischerkeller and Harnett Reference Fischerkeller and Harknett2019). However, other scholars believe the strategy of persistent engagement risks causing a “cybersecurity dilemma” by triggering a cyber arms race, provoking retaliation, or weaponizing information—outcomes that increase cyberinsecurity for both Washington and the international community (Buchanan Reference Buchanan2016; Klimburg Reference Klimburg2020).

This analysis favors the strategies of “defend forward” and “persistent engagement.” It suggests that the US would be better able to deter adversaries and secure cyberspace if it aggressively used its means to achieve global cyberhegemony. Given the scarcity of security in cyberspace, the US is unlikely to transition from a cyberpower maximizer to a status quo seeker even after achieving global cyberhegemony. Thus, the DoD’s 2018 cyberpolicy positions the US well to meet the particular challenges of cyberspace. Great powers are incentivized by the structure of this domain to pursue cyberhegemony, making interstate cyber-relations competitive and enabling an agreed form of competition that is not bounded by the DR’s balance-of-power DR logic implicit in CPT (Fischerkeller, Goldman, and Harknett Reference Fischerkeller, Goldman and Harknett2022, 50). This is where the key distinction lies between modified OR and CPT.

Although both modified OR and CPT are structural theories advocating persistent action in cyberspace, CPT theorists claim that their theory differs from structural IR theory because states utilize “cyber capabilities for unilateral exploitation, not brute force or coercion” (Fischerkeller, Goldman, and Harknett Reference Fischerkeller, Goldman and Harknett2022, 37). Yet the theory’s assumptions and prescriptions implicitly align with DR’s balance-of-power perspective. CPT argues that states seek initiative persistence via exploitative actions—infiltrating into enemy systems through vulnerabilities in these systems—that are calibrated to avoid a kinetic response and aim to achieve favorable cybersecurity conditions through cumulative strategic gains. These gains are contingent upon self-limiting behaviors defining the boundaries of agreed competition, which may be breached by “a relative shift in power between adversaries or a relative decline of a State across the global distribution of power” (Fischerkeller, Goldman, and Harknett Reference Fischerkeller, Goldman and Harknett2022, 52). Correspondingly, CPT ties the gaining of power and security to the ability of states to anticipate the relative vulnerability–exploitation balance in cyberspace (24). Here CPT clearly associates the stability of cyberspace or agreed competition with interstate power equilibrium.

CPT’s association of cyberstability with the balance-of-power perspective causes CPT to confront the same problem faced by DR: how can states work out the right amount of power (or strategic gains) needed to maintain the equilibrium?Footnote ¹⁴ OR argues that this is almost impossible, particularly in cyberspace, where the uncertainty that results from this dilemma is exacerbated by the secrecy of cyberpower and the impact of ever-shifting cybertechnology. Recognizing this, CPT contends that states can only anticipate the balance of initiative. But this would further increase uncertainty, since modified OR asserts that great powers cannot risk their security and survival by engaging in uncertain anticipatory behavior. Indeed, CPT scholars concede that “[t]he substance of cyber agreed competition is currently immature—mutual understandings of acceptable and unacceptable behaviors and of cyber key terrain are maturing slowly and narrowly” (Fisherkiller, Goldman, and Harknett Reference Fischerkeller, Goldman and Harknett2022, 50–52). Therefore, they accept that the rules of agreed competition can readily be breached.

Consequently, modified OR argues that states are driven by the structure of cyberspace to assume a worst-case scenario. This assumption is crucial because it explains why states constantly expand their cyberpower and pursue global cyberhegemony for security and strategic gains in cyberspace. Since structural incentives are the same for major states, they tacitly agree to compete in cyberspace as failing to do so will undermine their national power and (cyber)security while empowering their adversaries. Agreed competition, in contrast, is driven not by exploitation but by the will to expand and maximize power to achieve global cyberhegemony, cyberspace’s dominant behaviors. This implies that competitive cyberinteractions may persist under the leadership of a hegemon in cyberspace due to the inherent vulnerabilities, constant contact, and technological volatility of the domain. Answering the questions raised by cyberdominance consequently remains an empirical challenge.