The Politics of Vacuum Filling: Strategic Dynamics and Patterns of Power Transition in Contemporary International Relations

1. Introduction

The adage "nature abhors a vacuum," derived from physics, resonates profoundly within the study of international politics, where voids in power seldom remain unoccupied for extended durations (cf. Gilpin, 1981). When established powers retract, experience a decline in capacity, or undergo systemic collapse, competing state and non-state actors invariably maneuver to occupy the resultant void, thereby reshaping regional and global power configurations (Acharya, 2014; Lake, 2009). This paper investigates the politics of "filling the vacuum" as a fundamental and recurrent pattern in international relations, one that holds salience in the context of today's rapidly transforming global order (Modelski & Thompson, 2011).

The concept of power vacuums has garnered renewed scholarly and policy attention as the post-Cold War unipolar moment, largely characterized by American dominance, transitions towards a more competitive and fragmented multipolar system (Allison, 2017; Mearsheimer, 2019; Posen, 2014). The perceived relative decline of U.S. hegemony (Layne, 2018; MacDonald & Parent, 2018), the assertive ascent of China (Foot, 2020; Zhang, 2023), Russia's pursuit of revised geopolitical influence (Sakwa, 2022; Tsygankov, 2016), and the amplified agency of regional powers (Nolte & Wehner, 2020; Stewart-Ingersoll & Frazier, 2012) have collectively cultivated conditions conducive to intensified vacuum-filling competition across numerous domains and geographical expanses (Cooley & Nexon, 2020; Haass, 2017). From Central Asia and the Middle East to Africa and Latin America, and extending into maritime spaces and critical technological spheres, actors of varying capacities strategically maneuver to expand their influence in areas where established powers have demonstrably retrenched or where governance gaps exist (Buzan, 2011; Smith, 2022).

2. Objective

This study aims to critically examine the phenomenon of "power vacuums" in international relations. It seeks to analyze the strategic calculus states employ to expand their influence following the withdrawal or decline of other significant actors. The paper endeavors to identify discernible patterns of vacuum-filling behavior across military, political, economic, cultural, and technological spheres by integrating historical precedents with theoretical frameworks (Gilpin, 1981; Acharya, 2014). Ultimately, it aims to construct a comprehensive analytical framework for understanding multifaceted vacuum-filling policies in contemporary international relations and contribute to a nuanced understanding of power transitions, strategic competition, and evolving statecraft in 21st-century global politics (Beeson & Li, 2015; Johnson & Chen, 2021).

3. Methodology

This study employs a qualitative research methodology, primarily based on a critical review and synthesis of existing scholarly literature in international relations, political science, history, and strategic studies. It integrates historical analysis, examining precedents of vacuum-filling behavior from antiquity (Green, 2013; Grainger, 2010; Heather, 2007) to the Cold War era (Westad, 2007; Gaddis, 2005), to establish the enduring nature of the phenomenon. The research incorporates a comparative theoretical analysis, scrutinizing interpretations of vacuum-filling from diverse schools of thought, including realism (Waltz, 1979; Mearsheimer, 2001), liberal institutionalism (Keohane, 1984; Ikenberry, 2011), constructivism (Wendt, 1999; Finnemore & Sikkink, 1998), and power transition theory (Organski & Kugler, 1980), to provide a multifaceted understanding. Contemporary geopolitical dynamics are analyzed through selected case studies, such as the post-Soviet space (Asmus, 2002; Laruelle, 2018), the Middle East (Lynch, 2015), Afghanistan post-U.S. withdrawal (Mir, 2021; Afzal, 2021), and technological competition in the Global South (Hillman, 2021; Segal, 2020), to illustrate current patterns and strategies of vacuum-filling. The analysis relies on established academic works, policy reports, and contemporary geopolitical commentary to identify patterns, strategies, challenges (Kennedy, 1987; Scott, 1998), and future trends (Kupchan, 2012; Bremmer, 2021) associated with vacuum-filling dynamics.

4. Historical Roots of Vacuum-Filling Policies

The strategic imperative to fill power vacuums is deeply embedded in the historical record, manifesting across varied civilizational contexts and historical epochs. This section traces significant historical exemplars of vacuum-filling behavior, underscoring the enduring nature of this strategic pattern.

4.1. Ancient and Classical Precedents

Vacuum-filling dynamics are observable from antiquity. Following the disintegration of the Achaemenid Persian Empire in the 4th century BCE, the ensuing power void in the Near East and Central Asia was swiftly contested and occupied by Alexander the Great's successors, notably the Seleucids and Ptolemies, who vied for control over former Persian territories (Green, 2013; Grainger, 2010). Similarly, as the Western Roman Empire experienced its gradual decline and eventual collapse in the 5th century CE, various Germanic tribes, the Huns, and other groups exploited Rome's diminishing capacity, establishing new political entities within territories previously under Roman administration (Heather, 2007; Ward-Perkins, 2005).

4.2. The Colonial Era and Imperial Competition

The early modern period witnessed vacuum-filling on an unprecedented global scale as European powers engaged in intense competition to establish colonial dominance across the Americas, Africa, and Asia. The decline or subjugation of indigenous empires and polities created perceived opportunities for European expansion, with rival colonial powers hastening to claim territories and resources before their competitors could (Darwin, 2008; Burbank & Cooper, 2010). The "Scramble for Africa" in the late 19th century serves as a stark illustration of this dynamic, wherein European powers, following the Berlin Conference of 1884-1885, partitioned the continent, asserting colonial control over vast territories previously beyond their direct influence (Pakenham, 1992).

4.3. Post-Ottoman Vacuum and the Middle East

The dissolution of the Ottoman Empire following World War I represents a pivotal instance of vacuum-filling with profound and lasting geopolitical consequences. The withdrawal of Ottoman authority from significant swathes of the Middle East and parts of the Balkans created a geopolitical vacuum that European powers, chiefly Britain and France, moved decisively to fill (Fromkin, 1989; Rogan, 2015). The 1916 Sykes-Picot Agreement stands as a testament to the calculated, albeit controversial, planning for post-Ottoman vacuum-filling, dividing the Empire's Arab provinces into spheres of British and French influence and control (Barr, 2011). This arbitrary redrawing of the Middle Eastern map established state boundaries and power arrangements that continue to shape, and often destabilize, regional dynamics in the present day (Owen, 2004).

4.4. Cold War Competition

The Cold War era (circa 1947-1991) epitomizes perhaps the most systematic and globalized manifestation of vacuum-filling politics. As European colonial powers progressively withdrew from their overseas possessions in the aftermath of World War II, the United States and the Soviet Union engaged in intensive, ideologically charged competition to fill the resultant power vacuums across Asia, Africa, and Latin America (Westad, 2007; Gaddis, 2005). The Truman Doctrine of 1947, which committed the United States to supporting nations purportedly threatened by Soviet expansionism, explicitly embraced a vacuum-filling logic by pledging to prevent Communist forces from exploiting power vacuums created by decolonization and post-war instability (Leffler, 2007). Throughout the Cold War, both superpowers systematically endeavored to establish and expand their influence in newly independent states. This involved supporting aligned regimes, providing substantial military and economic assistance, and, in numerous instances, engaging in proxy conflicts to prevent the opposing bloc from gaining strategic advantages (Zubok & Pleshakov, 2008). This bipolar competition established enduring patterns of external involvement and, in some cases, dependency, which significantly shaped the political trajectories of many developing nations for decades (Engerman, 2010).

This historical overview demonstrates that vacuum-filling is a recurrent, rather than novel, pattern in international relations. Contemporary strategies for filling power vacuums build upon these historical precedents while adapting to the unique complexities and conditions of the current international system.

5. Theoretical Frameworks for Understanding Vacuum-Filling

Diverse theoretical traditions within international relations offer distinct, though often complementary, interpretations of vacuum-filling behavior, each highlighting various facets of this complex phenomenon. This section examines how major theoretical schools conceptualize and elucidate the politics of filling power vacuums.

Table 1. Comparative Summary of Major IR Theories on Vacuum-Filling.

Theoretical School	Main Explanation of Vacuum-Filling	Key Mechanisms	Typical Examples	Representative Authors
Realism	States seek power/security; vacuums are threats or opportunities	Military, economic, alliances	NATO in E. Europe, US in Middle East	Waltz (1979), Mearsheimer (2001, 2019)
Liberal Institutionalism	Institutions can manage vacuums, mitigate conflict	Multilateralism, economic interdependence, IOs	EU in E. Europe, ASEAN in SE Asia	Keohane (1984), Ikenberry (2011)
Constructivism	Meaning of "vacuum" socially constructed; shaped by identity/norms	Norm diffusion, identity politics	China's BRI as "win-win"/identity	Wendt (1999), Finnemore & Sikkink (1998)
Power Transition Theory	Vacuums emerge during power shifts; contest by rising/declining powers	Systemic rivalry, hegemonic order	Soviet collapse, US-China competition	Organski & Kugler (1980), Tammen et al. (2000)

Note: Adapted from Waltz (1979); Keohane (1984); Wendt (1999); Organski & Kugler (1980); Mearsheimer (2019); Ikenberry (2011); Finnemore & Sikkink (1998); Tammen et al. (2000).

Table 1. Comparative Summary of Major IR Theories on Vacuum-Filling.

Theoretical School	Main Explanation of Vacuum-Filling	Key Mechanisms	Typical Examples	Representative Authors
Realism	States seek power/security; vacuums are threats or opportunities	Military, economic, alliances	NATO in E. Europe, US in Middle East	Waltz (1979), Mearsheimer (2001, 2019)
Liberal Institutionalism	Institutions can manage vacuums, mitigate conflict	Multilateralism, economic interdependence, IOs	EU in E. Europe, ASEAN in SE Asia	Keohane (1984), Ikenberry (2011)
Constructivism	Meaning of "vacuum" socially constructed; shaped by identity/norms	Norm diffusion, identity politics	China's BRI as "win-win"/identity	Wendt (1999), Finnemore & Sikkink (1998)
Power Transition Theory	Vacuums emerge during power shifts; contest by rising/declining powers	Systemic rivalry, hegemonic order	Soviet collapse, US-China competition	Organski & Kugler (1980), Tammen et al. (2000)

Note: Adapted from Waltz (1979); Keohane (1984); Wendt (1999); Organski & Kugler (1980); Mearsheimer (2019); Ikenberry (2011); Finnemore & Sikkink (1998); Tammen et al. (2000).

5.1. Realist Perspectives

Realist theories, in their various iterations, provide arguably the most direct explanation for vacuum-filling behavior, viewing it as an almost inevitable consequence of power politics within an anarchic international system (Donnelly, 2000). Classical realists, such as Hans Morgenthau (1948/2006), would interpret vacuum-filling as a manifestation of states' inherent drive to maximize power and secure their interests whenever strategic opportunities emerge. From this viewpoint, power vacuums represent both enticing opportunities for influence expansion and critical threats that rivals might exploit if not preempted (Taliaferro et al., 2009).

Structural realists, or neorealists, following the foundational work of Kenneth Waltz (1979), emphasize the systemic pressures that compel states to fill power vacuums. The anarchic structure of the international system, lacking central authority, creates potent incentives for states to enhance their relative power and security by expanding into available spaces, lest competitors gain a strategic advantage. John Mearsheimer's (2001) offensive realism posits that great powers are inherently revisionist and will naturally seek to maximize their relative power, inevitably moving to exploit vacuums left by retreating or declining rivals.

Conversely, defensive realists, such as Stephen Walt (1987), contend that states may fill vacuums primarily for security-driven, preventive reasons rather than purely for power aggrandizement. In this interpretation, vacuum-filling often represents a defensive strategy aimed at denying strategic spaces to potential adversaries who might otherwise exploit them to project threatening influence or upset the existing balance of power (Schweller, 2016). Neoclassical realism further refines these perspectives by incorporating domestic-level variables, suggesting that systemic pressures are filtered through state structures and leadership perceptions, influencing how states identify and respond to power vacuums (Rose, 1998).

5.2. Liberal Institutionalist Interpretations

Liberal institutionalist theories offer a more optimistic, or at least nuanced, interpretation of vacuum-filling dynamics, suggesting that cooperative frameworks and international institutions can mitigate zero-sum competition (Keohane, 1984; Martin & Simmons, 2012). From this perspective, international institutions and regimes can play a crucial role in managing power transitions and filling vacuums in ways that maintain systemic stability and potentially benefit multiple actors (Ikenberry, 2011). Rather than invariably generating conflict, power vacuums might be addressed through multilateral cooperation, institutionalized norms, and shared governance mechanisms that constrain raw power politics.

G. John Ikenberry argues that liberal international orders, even under strain, can facilitate peaceful power transitions by providing institutional frameworks within which rising powers can gain influence and status without necessarily overturning the entire system. In this view, vacuum-filling need not be inherently conflictual if it is embedded within rules-based orders that accommodate shifts in relative power while preserving core institutional arrangements and norms of cooperation (Ikenberry, 2001; Ikenberry, 2018).

Furthermore, economic interdependence, a central tenet of liberal theory, may modify vacuum-filling behavior by increasing the costs of aggressive competition and incentivizing cooperative, or at least non-conflictual, approaches (Keohane & Nye, 1977/2012). Complex economic ties and shared interests among major powers can temper zero-sum calculations when addressing geopolitical vacuums, promoting solutions that emphasize mutual gain or shared stewardship.

5.3. Constructivist Approaches

Constructivist theories enrich the understanding of vacuum-filling by emphasizing the pivotal role of ideas, identities, norms, and social constructions (Wendt, 1999; Finnemore & Sikkink, 1998). From this perspective, how states perceive and respond to power vacuums is contingent not only on material factors (like military or economic capabilities) but also on ideational elements such as historical narratives, collective identity constructions, and prevailing normative frameworks (Katzenstein, 1996). Constructivists argue that "vacuums" themselves are, in part, social construction spaces defined as "empty" or "available" based on intersubjective understandings of order, legitimacy, and sovereignty. How actors interpret these spaces, and what responses they deem appropriate or legitimate, depends on socially constructed meanings, shared understandings, and discursive practices rather than solely on objective material conditions (Hopf, 2002).

Identity factors significantly shape which vacuum states perceive as relevant to their core interests and how they approach the task of filling them. States with specific role conceptions—such as "regional leader," "great power," "norm entrepreneur," or "champion of particular values"—may feel compelled by these identities to fill certain vacuums that align with their self-perceived roles and responsibilities on the international stage (Breuning, 2011). Historical relationships, cultural affinities, ideological commitments, and shared normative beliefs further influence which vacuums state prioritize and the methods they employ in addressing them (Adler & Barnett, 1998).

5.4. Power Transition Theory and Hegemonic Stability

Power transition theory offers specific insights into vacuum-filling dynamics, particularly during periods of significant systemic change (Organski & Kugler, 1980; Tammen et al., 2000). This theory suggests that international stability is often contingent upon clear hierarchies of power. Power vacuums and the uncertainties they generate can act as triggers for conflict, especially as rising powers challenge established arrangements and declining powers struggle to maintain their positions. From this perspective, vacuum-filling represents a critical mechanism through which power transitions manifest, as declining hegemons or dominant powers withdraw from regions or functional domains, and rising powers move to assert new influence and potentially reshape the rules of the game (DiCicco & Levy, 2003). Hegemonic stability theory, closely associated with scholars like Robert Gilpin (1981) and Charles Kindleberger (1973), similarly posits that international order often requires a dominant power (a hegemon) willing and able to provide public goods, enforce rules, and maintain systemic stability. When hegemonic powers decline or voluntarily retract from their global or regional commitments, the resulting vacuums may trigger intensified competition among potential successors or regional aspirants seeking to establish new orders aligned with their interests, values, and preferred governance models.

These diverse theoretical perspectives—realist, liberal, constructivist, and theories of power transition—are not necessarily mutually exclusive but rather offer complementary lenses for analyzing the multifaceted phenomenon of vacuum-filling. A comprehensive understanding requires an integrated approach that acknowledges the interplay of material power considerations, institutional contexts, ideational factors, and historical path dependencies in shaping how states perceive and respond to power vacuums.

6. Patterns of Vacuum-Filling in International Relations

Vacuum-filling strategies are manifested across a multitude of domains, employing a diverse array of instruments of power and influence. This section identifies distinct patterns of vacuum-filling behavior evident in contemporary international relations, illustrating how states deploy different tools to expand their influence into spaces where established powers have withdrawn, declined, or where governance is weak or contested.

Table 2. Comparative Patterns of Contemporary Vacuum-Filling.

Pattern/Domain	Primary Tools	Typical Actors	Recent Examples	Citation
Military	Troop deployment, alliances	US, Russia, Turkey	Russia in Syria, NATO in E. Europe	Trenin (2018); Asmus (2002)
Political/Diplomatic	Diplomacy, mediation, recognition	China, Russia, EU	China in Africa, Russia in Venezuela	Shambaugh (2013); Ellis (2019)
Economic	Aid, loans, FDI, infrastructure	China, Japan, Gulf States	BRI, Japan in SE Asia	Chatzky & McBride (2020); Jimbo (2019)
Cultural/Ideological	Media, education, soft power	US, China, Russia	Confucius Institutes, RT, Fulbright	Melissen & Sarti (2021); Elswah & Howard (2020)
Technological	Digital infrastructure, standards	China, US, EU	5G rollout, Digital Silk Road	Hillman (2021); Segal (2020)

Note: Adapted from Trenin (2018); Shambaugh (2013); Chatzky & McBride (2020); Melissen & Sarti (2021); Hillman (2021).

Table 2. Comparative Patterns of Contemporary Vacuum-Filling.

Pattern/Domain	Primary Tools	Typical Actors	Recent Examples	Citation
Military	Troop deployment, alliances	US, Russia, Turkey	Russia in Syria, NATO in E. Europe	Trenin (2018); Asmus (2002)
Political/Diplomatic	Diplomacy, mediation, recognition	China, Russia, EU	China in Africa, Russia in Venezuela	Shambaugh (2013); Ellis (2019)
Economic	Aid, loans, FDI, infrastructure	China, Japan, Gulf States	BRI, Japan in SE Asia	Chatzky & McBride (2020); Jimbo (2019)
Cultural/Ideological	Media, education, soft power	US, China, Russia	Confucius Institutes, RT, Fulbright	Melissen & Sarti (2021); Elswah & Howard (2020)
Technological	Digital infrastructure, standards	China, US, EU	5G rollout, Digital Silk Road	Hillman (2021); Segal (2020)

Note: Adapted from Trenin (2018); Shambaugh (2013); Chatzky & McBride (2020); Melissen & Sarti (2021); Hillman (2021).

6.1. Military Vacuum-Filling

Military approaches represent perhaps the most conspicuous and direct form of vacuum-filling. When established powers withdraw military forces, retract security guarantees, or reduce their defense commitments in strategically significant regions, other actors often move to establish their own military presence or forge new security relationships. This pattern was evident in NATO's eastward expansion following the dissolution of the Warsaw Pact, which aimed to fill the perceived security vacuum in Eastern Europe created by Soviet withdrawal, albeit with contentious consequences (Goldgeier & McFaul, 2003; Asmus, 2002). More recently, Russia's military intervention in Syria commencing in 2015 effectively filled a vacuum created, in part, by American reluctance to become deeply militarily involved in the Syrian conflict, thereby allowing Moscow to secure and strengthen its military posture and influence in the Middle East (Trenin, 2018). Military vacuum-filling typically involves activities such as deploying armed forces, establishing forward operating bases or access agreements, providing arms transfers and military training to local allies or proxies, conducting joint military exercises, or establishing formal security arrangements and alliances. Such approaches are designed not only to project hard power and secure strategic interests but also to demonstrate commitment to regional security (or a particular vision thereof), influence local political developments, and deter or complicate rival powers' attempts to establish their own military presence.

6.2. Political and Diplomatic Vacuum-Filling

Political and diplomatic vacuum-filling centers on cultivating and strengthening relationships with governments, political elites, and influential non-state actors in regions undergoing power transitions or experiencing governance deficits. This pattern involves bolstering diplomatic ties and representation, providing political support to aligned domestic forces, offering mediation services in conflicts, and expanding participation and influence within regional and international forums and institutions.

China's extensive diplomatic outreach and strategic partnerships with countries traditionally within Western spheres of influence, particularly across Africa, Latin America, and parts of the Pacific Islands, exemplifies this approach (Shambaugh, 2013). Beijing has systematically expanded its diplomatic engagement, established new partnerships and enhanced existing ones in areas where American or European influence has been perceived as waning or insufficient.

Similarly, Russia has actively worked to strengthen political relationships with certain Latin American countries, such as Venezuela, Cuba, and Nicaragua, arguably exploiting diminished U.S. attention or policy shifts in the region (Ellis, 2019). Political vacuum-filling may target not only state-to-state relationships but also sub-state groups, opposition movements, and civil society organizations. External powers often cultivate ties with political parties, influential community leaders, and other domestic actors to enhance their leverage and influence within societies experiencing political transitions, instability, or contested governance.

6.3. Economic Vacuum-Filling

Economic instruments have become increasingly central to contemporary vacuum-filling strategies, particularly for rising powers possessing significant financial resources and developmental expertise. Economic vacuum-filling involves the strategic deployment of trade agreements, foreign direct investment, concessional and non-concessional loans, development aid programs, and large-scale infrastructure development projects to establish and consolidate influence in regions where established economic partners have reduced their engagement or where significant developmental needs remain unmet.

China's Belt and Road Initiative (BRI) stands as perhaps the most ambitious contemporary example of an economic vacuum-filling strategy, directing vast sums into infrastructure investments across Asia, Africa, Europe, Latin America, and beyond (Chatzky & McBride, 2020). The BRI explicitly targets infrastructure gaps and development needs often unaddressed by traditional Western institutions or private capital, thereby creating economic dependencies, supply chain integration, and political leverage through massive investments in transportation networks, energy projects, and digital communications infrastructure (World Bank, 2019).

Other examples include Russia's use of energy resources, pipelines, and nuclear technology to maintain or expand influence in its "near abroad" and further afield, Japan's sustained infrastructure investments and development assistance across Southeast Asia (Jimbo, 2019), and the financial diplomacy and investment strategies of Gulf states in the Middle East, North Africa, and the Horn of Africa (Young, 2021). Economic vacuum-filling aims to create influence through mechanisms such as indebtedness, trade dependencies, control over critical infrastructure, market access, and the shaping of development pathways, often proving more durable and less overtly provocative than direct military approaches.

6.4. Cultural and Ideological Vacuum-Filling

Cultural and ideological vacuum-filling targets the less tangible but highly significant realm of ideas, values, norms, and identities. This pattern involves the promotion of political models, cultural values, educational systems, governance philosophies, or ideological frameworks in societies perceived to be undergoing identity transitions, normative uncertainty, or ideological contestation. During the Cold War, both superpowers engaged extensively in ideological vacuum-filling, promoting competing visions of political and economic organization—liberal democracy versus Marxist-Leninism (Westad, 2007; Saunders, 2011). In the contemporary context, this pattern persists, albeit with different content and actors. Western powers continue to promote liberal democratic values, human rights, and good governance norms in transitional societies, often through democracy assistance programs and support for civil society.

Conversely, powers like Russia and China increasingly offer alternative models that emphasize state sovereignty, state-led development, political stability, and "traditional values" over liberal individual rights, often framed as more suitable for non-Western contexts (Cooley, 2015). Cultural vacuum-filling employs a range of tools, including state-sponsored international media networks (e.g., RT, CGTN), educational exchange programs (e.g., Confucius Institutes, Fulbright Program), language promotion initiatives, cultural centers, and support for aligned civil society organizations or religious groups. These efforts aim to shape ideational environments, cultivate sympathetic elites, and build long-term influence within contested social and political spaces.

6.5. Technological Vacuum-Filling

A more recent but increasingly critical pattern involves technological vacuum-filling—the strategic effort to establish dominance or significant influence in emerging technological domains and digital infrastructure, particularly where standards, governance frameworks, and control remain contested or underdeveloped. This pattern has gained prominence with the escalating strategic importance of technologies such as 5G and future-generation telecommunications networks, artificial intelligence (AI), quantum computing, biotechnology, and space-based capabilities.

The intense U.S.-China competition over the global rollout of 5G infrastructure exemplifies technological vacuum-filling, with both powers vying to establish their preferred technological standards, systems, and supply chains in third countries, thereby shaping future digital ecosystems (Segal, 2020). China's Digital Silk Road initiative, an extension of the BRI, specifically targets technological gaps and digital infrastructure needs in developing nations, offering digital connectivity solutions, smart city systems, surveillance technologies, and e-government platforms that can create long-term technological dependencies and data flows favorable to Beijing (Hillman, 2021).

Technological vacuum-filling aims to create influence through mechanisms such as control of critical information and communication technology (ICT) infrastructure, the ability to set technical standards (which create path dependencies), privileged access to data flows, and the creation of technological ecosystems that are difficult for users or countries to exit once adopted. This form of influence can have profound implications for economic competitiveness, national security, and societal development.

These distinct patterns of vacuum-filling—military, political, economic, cultural/ideological, and technological—often operate concurrently and are frequently interconnected within a state's broader strategic approach. Contemporary great powers and aspiring regional leaders typically employ multidimensional "smart power" strategies, combining elements from several of these categories in comprehensive efforts to fill perceived power vacuums. The specific mix of instruments deployed varies based on a state's capabilities and resources, its strategic culture and foreign policy traditions, the characteristics of the target region or domain, and the prevailing international and local conditions.

7. Case Studies of Contemporary Vacuum-Filling

This section examines specific instances of vacuum-filling within the contemporary international system, illustrating how the patterns identified previously manifest in particular regional and functional contexts. These cases highlight the complex interplay of global and regional actors, and the diverse strategies employed.

Table 3. Comparative Case Studies: Vacuum-Filling Dynamics (1991–Present).

Region/Doman	Primary Vacuum	Leading Fillers	Tools Used	Outcome/Trend	Key Reference
Post-Soviet Space	Soviet collapse	EU, NATO, Russia, China	Integration, military, BRI	Ongoing competition, hybrid strategies	Asmus (2002); Laruelle (2018)
Middle East	US retrenchment	Russia, Iran, Turkey, Gulf States	Military, proxies, finance	Regional fragmentation, proxy wars	Lynch (2015); Kozhanov (2018)
Afghanistan (2021)	US withdrawal	China, Russia, Iran, Pakistan	Diplomatic, economic, security	Multi-power engagement, uncertainty	Mir (2021); Afzal (2021)
Global South (Tech)	Digital infrastructure gap	China, US, EU	Tech export, standards, FDI	Competing digital ecosystems	Hillman (2021); Segal (2020)

Note: Adapted from Lynch (2015); Asmus (2002); Laruelle (2018); Mir (2021); Hillman (2021).

Table 3. Comparative Case Studies: Vacuum-Filling Dynamics (1991–Present).

Region/Doman	Primary Vacuum	Leading Fillers	Tools Used	Outcome/Trend	Key Reference
Post-Soviet Space	Soviet collapse	EU, NATO, Russia, China	Integration, military, BRI	Ongoing competition, hybrid strategies	Asmus (2002); Laruelle (2018)
Middle East	US retrenchment	Russia, Iran, Turkey, Gulf States	Military, proxies, finance	Regional fragmentation, proxy wars	Lynch (2015); Kozhanov (2018)
Afghanistan (2021)	US withdrawal	China, Russia, Iran, Pakistan	Diplomatic, economic, security	Multi-power engagement, uncertainty	Mir (2021); Afzal (2021)
Global South (Tech)	Digital infrastructure gap	China, US, EU	Tech export, standards, FDI	Competing digital ecosystems	Hillman (2021); Segal (2020)

Note: Adapted from Lynch (2015); Asmus (2002); Laruelle (2018); Mir (2021); Hillman (2021).

7.1. Post-Soviet Space: Enduring Competition and Shifting Dynamics

The collapse of the Soviet Union in 1991 created arguably the most significant geopolitical vacuum of the late 20th century, triggering intensive and sustained competition to shape the political, economic, and security orientations of the newly independent states (Bremmer & Charap, 2007). This vast region continues to be a theater for competing vacuum-filling strategies by multiple actors. Western institutions, notably NATO and the European Union, moved to fill aspects of the post-Soviet vacuum through policies of enlargement and association, integrating former Warsaw Pact countries and the Baltic states into Western security, economic, and normative structures (Asmus, 2002; Schimmelfennig, 2005). This institutional expansion aimed to fill perceived security and governance vacuums in Central and Eastern Europe, fundamentally realigning these countries towards Western models, a process viewed by Russia with increasing alarm.

Russia, following a period of relative retrenchment in the 1990s, adopted increasingly assertive policies under Vladimir Putin to re-establish and maintain its influence in what it terms its "near abroad" or "privileged sphere of influence" (Trenin, 2011; Mankoff, 2009). Moscow has employed a multidimensional approach, including direct military interventions (e.g., Georgia in 2008, Ukraine since 2014), leveraging energy politics through control of gas supplies and pipeline infrastructure, supporting separatist regions and frozen conflicts, promoting integration projects like the Eurasian Economic Union (EAEU), and conducting extensive media influence and disinformation operations (Roberts, 2017). These policies represent a concerted attempt to counter and reverse perceived Western vacuum-filling in regions Russia considers vital to its security and identity.

China has progressively expanded its economic footprint in Central Asia, primarily through the Belt and Road Initiative, filling economic and infrastructure vacuums left by Soviet collapse and, in some areas, limited Western or Russian investment (Laruelle, 2018; Cooley, 2012). By predominantly focusing on economic instruments—large-scale infrastructure projects, trade, and investment—rather than overt military or direct political intervention, Beijing has established growing influence while, for the most part, navigating carefully around Russia's established security prerogatives in the region, though this dynamic is evolving.

This complex case illustrates how different powers employ distinct vacuum-filling approaches based on their comparative advantages, strategic cultures, and perceived interests: Western powers emphasizing institutional integration and normative influence; Russia utilizing military power, energy leverage, and political coercion; and China deploying primarily economic instruments and infrastructure diplomacy.

7.2. Middle East: Regional Rivalries Amidst Shifting Global Engagement

A perceived reduction in sustained American commitment and direct military involvement in the Middle East, particularly following the 2011 "Arab Spring" uprisings and subsequent shifts in U.S. military posture and foreign policy priorities, has created opportunities for multiple regional and global actors to expand their influence (Lynch, 2015). This case demonstrates how regional powers, alongside global players, engage vigorously in vacuum-filling behavior, often leading to heightened regional instability.

Russia's military intervention in Syria from 2015 onwards is a salient example of direct vacuum-filling, occurring partly in response to U.S. hesitancy for deep, direct military engagement in the Syrian civil war. Moscow's robust military support for the Assad regime not only preserved its ally but also re-established Russia as an indispensable actor in Middle Eastern security dynamics, securing valuable military bases, enhancing diplomatic leverage, and projecting renewed regional status (Kozhanov, 2018).

Iran has systematically expanded its influence across the "Shia Crescent" and beyond, primarily through its support for a network of non-state actors and proxy forces in Iraq, Syria, Lebanon, Yemen, and Palestine (Alfoneh, 2013; Ostovar, 2019). Tehran's "forward defense" strategy and cultivation of these groups have effectively filled security and governance vacuums created by state weakness, internal conflicts, and the collapse of previous power structures, establishing a significant arc of Iranian influence across the region.

Turkey, under President Erdoğan, has likewise pursued a more assertive and independent regional policy, moving to fill perceived vacuums by establishing military positions in northern Syria and Libya, supporting aligned political movements (such as factions of the Muslim Brotherhood), and challenging traditional powers for influence in the Eastern Mediterranean and other areas (Tanchum, 2020). Ankara's actions aim to establish Turkey as a distinct power center, less constrained by its traditional Western alliances.

Gulf states, particularly Saudi Arabia, the United Arab Emirates (UAE), and Qatar, have also significantly expanded their regional activities, employing their substantial financial resources, engaging in military interventions (e.g., Yemen), and utilizing diplomatic and informational influence to shape political outcomes in countries like Egypt, Libya, Sudan, and the Horn of Africa (Young, 2021; Ulrichsen, 2020). This has led to complex intra-Gulf rivalries that further complicate the regional landscape.

This case demonstrates how vacuum-filling often involves multiple, competing actors simultaneously, creating intricate and frequently unstable dynamics as various powers establish overlapping and contested spheres of influence, leading to proxy conflicts and a fragmented regional order.

7.3. U.S. Withdrawal from Afghanistan: Rapid Realignment and Regional Power Plays

The precipitous U.S. military withdrawal from Afghanistan in August 2021, culminating in the Taliban's rapid takeover, created a stark and immediate power vacuum after two decades of American and NATO military presence (Mahinazi & Ibrahimi, 2022). This event triggered swift maneuvers by regional powers to protect their interests, manage potential threats, and establish influence with the new Taliban-led government. Even prior to the final U.S. departure, neighboring and regional powers including China, Russia, Iran, and Pakistan had initiated or intensified diplomatic engagement with the Taliban, positioning themselves to influence Afghanistan's future political and security arrangements (Mir, 2021). Following the Taliban's assumption of power, these states quickly moved to establish pragmatic working relationships with the new regime, while simultaneously seeking assurances against transnational terrorism, refugee flows, and broader regional instability.

China's approach has primarily focused on potential economic engagement, particularly concerning Afghanistan's untapped mineral resources and its potential, albeit challenging, integration into the Belt and Road Initiative. Beijing has emphasized pragmatic cooperation on issues of mutual interest, such as counter-terrorism (specifically regarding Uyghur militants), while cautiously avoiding the deep security commitments that proved so costly to previous external powers (Zhou, 2021).

Russia has prioritized security cooperation to prevent the spillover of terrorism and drug trafficking into Central Asia, leveraging its existing relationships with Central Asian states (several of which are CSTO members) and conducting military exercises in the region to underscore its continued security relevance and capabilities (Stronski, 2021).

Pakistan, which has long maintained complex and often opaque ties with the Taliban, moved to consolidate its influence with the new regime while simultaneously facing the challenges of managing a volatile border, increased refugee flows, and the potential emboldening of militant groups within Pakistan itself (Afzal, 2021).

This case vividly demonstrates how vacuum-filling follows predictable patterns even in rapidly evolving and highly uncertain circumstances. Regional powers quickly maneuvered to establish influence by leveraging their comparative advantages: China through its economic potential and infrastructure capabilities, Russia through its security relationships and military posture in Central Asia, and neighboring states like Pakistan and Iran through their historical, cultural, and geographical proximities.

7.4. Technological Competition in the Global South: The New Frontier of Influence

The contested development and deployment of digital infrastructure in developing nations across the Global South represents a distinct and increasingly crucial type of vacuum-filling, focused on establishing technological rather than purely territorial control or traditional geopolitical dominance (Melissen & Sarti, 2021). This case illustrates how vacuum-filling is progressively extending beyond conventional geopolitical concerns into emerging and foundational technological domains.

China has systematically and rapidly expanded its digital footprint across Africa, Southeast Asia, Latin America, and other parts of the developing world, largely through its Digital Silk Road (DSR) initiative, which complements the physical infrastructure focus of the BRI (Hillman, 2021; Kurlantzick, 2020). Chinese technology companies, notably Huawei and ZTE, often with state backing, have built extensive telecommunications networks (including 4G and 5G infrastructure), data centers, smart city systems, and surveillance platforms in numerous countries where Western technology firms have had a more limited presence or have been outcompeted on price or speed of deployment. This digital infrastructure development effectively fills technological vacuums and meets genuine connectivity needs in developing regions, while simultaneously embedding China's technical standards, creating potential avenues for intelligence gathering, and fostering long-term technological dependencies and data flows favorable to Chinese interests (Segal, 2020).

The United States and its democratic allies (e.g., the EU, Japan, Australia) have, somewhat belatedly, responded with initiatives aimed at providing alternatives to China's digital expansion. Programs like the Build Back Better World (B3W) (now evolved into the Partnership for Global Infrastructure and Investment - PGII) and the EU's Global Gateway strategy seek to offer alternative financing, technology, and technical assistance for infrastructure development, including digital connectivity, emphasizing values such as transparency, sustainability, data privacy, and high labor standards (White House, 2021). These initiatives explicitly aim to fill infrastructure and technological gaps with models that purportedly embed Western democratic values and governance principles.

This technological competition extends beyond physical infrastructure to encompass critical areas such as digital governance models, data localization policies, and international standard-setting for emerging technologies like AI and IoT. China actively promotes its concept of "cyber sovereignty" and state-centric internet governance in international forums, while Western powers generally advocate for more open, multi-stakeholder internet governance approaches (Segal, 2018). Both sides are effectively seeking to fill normative and regulatory vacuums regarding how digital technologies should be governed, deployed, and utilized on a global scale.

This case underscores how vacuum-filling increasingly encompasses non-territorial domains were establishing early influence in setting standards, building infrastructure, and shaping governance frameworks can create lasting strategic advantages through network effects, technological path dependencies, and control over critical data and information flows.

These diverse case studies—from the post-Soviet space to the Middle East, Afghanistan, and the technological competition in the Global South—collectively illustrate the multifaceted nature of contemporary vacuum-filling strategies. Despite variations in regional context, the specific actors involved, and the primary tools employed, similar underlying patterns emerge: opportunistic moves by various powers to establish or expand influence when established powers withdraw or governance gaps appear; complex competition, and sometimes cautious cooperation, among multiple actors possessing different comparative advantages; and an increasing reliance on multidimensional approaches that integrate hard power, soft power, and increasingly, "sharp power" instruments (Walker & Ludwig, 2018).

9. Challenges and Limitations of Vacuum-Filling Policies

Despite their apparent strategic appeal and potential benefits, policies aimed at filling power vacuums are fraught with significant challenges, inherent limitations, and considerable risks that can constrain their effectiveness, undermine their sustainability, and lead to unintended negative consequences. This section examines the primary difficulties that states and other actors encounter when attempting to project influence into and manage power vacuums.

9.1. Security Dilemmas and Escalation Risks

Vacuum-filling initiatives, particularly those involving military or overt political measures, frequently trigger security dilemmas and intensify competitive dynamics that can escalate beyond the initial intentions of the actors involved (Jervis, 1978; Glaser, 2010). When one power moves to fill a perceived vacuum, other regional or global actors often interpret this action as threatening to their own interests, prompting them to respond with countermeasures. This action-reaction cycle can lead to arms races, heightened tensions, proxy conflicts, and even direct confrontation, thereby destabilizing the region further.

NATO's eastward expansion, intended by its proponents to fill a security vacuum in Central and Eastern Europe following Soviet collapse and enhance regional stability, was perceived by Russia as a form of strategic encirclement and a direct threat to its security interests. This perception arguably contributed to motivating more assertive and revisionist Russian policies towards its "near abroad," including actions in Georgia and Ukraine (Mearsheimer, 2014; Sakwa, 2015).

The risk of unintended escalation is particularly acute in situations where multiple powers simultaneously attempt to fill the same vacuum through incompatible or directly competing strategies. In Syria, for example, the overlapping and often conflicting vacuum-filling operations of Russia, Iran, Turkey, the United States, and various Gulf states created numerous dangerous friction points, deconfliction challenges, and military incidents, despite some efforts to coordinate or at least avoid direct clashes.

9.2. Economic Constraints and Risks of Overextension

Effective and sustained vacuum-filling, especially across multiple domains or regions, typically requires substantial and prolonged resource commitments, financial, military, and diplomatic, that may strain even the economic capabilities of powerful states. The historical phenomenon of "imperial overextension," where the costs of maintaining influence in peripheral areas or contested vacuums eventually exceed sustainable levels, has repeatedly undermined great powers throughout history (Kennedy, 1987; Gilpin, 1981).

China's ambitious Belt and Road Initiative, while transformative in many respects, has encountered significant economic sustainability challenges. Numerous projects have faced issues related to debt servicing difficulties for recipient countries, questions about commercial viability, lower-than-expected economic returns, and accusations of creating "debt traps" (Hillman, 2019). These economic constraints and criticisms have compelled Beijing to adjust its approach, emphasizing "high-quality," "small and beautiful" projects, and adopting more commercially disciplined and risk-averse lending practices, thereby demonstrating the practical limitations of even large-scale economic vacuum-filling (Bräutigam, 2020).

Similarly, Russia's multiple simultaneous commitments—including the protracted war in Ukraine, ongoing operations in Syria, engagement in parts of Africa, and support for allies in Latin America—have imposed significant costs on an economy already constrained by international sanctions, structural weaknesses, and fluctuating commodity prices (Connolly, 2018). These economic limitations inevitably restrict Moscow's capacity to sustain extensive and ambitious vacuum-filling operations across multiple fronts indefinitely.

9.3. Political Resistance, Legitimacy Challenges, and Local Agency

Powers attempting to fill vacuums frequently encounter significant political resistance from local populations, nationalistic elites, and civil society groups who may resent perceived external interference, fear neocolonial domination, or have their own agendas for the "empty" space. The historical legacy of colonialism and post-colonial sensitivities has made many societies particularly wary of new forms of foreign control or influence, even when such interventions are packaged as partnerships, development assistance, or security cooperation (Ayoob, 2002; Barkawi, 2016).

Chinese infrastructure projects under the BRI, for example, have faced growing backlash and political opposition in several host countries, from Malaysia and Sri Lanka to Kenya and Montenegro. Concerns about debt sustainability, environmental degradation, opaque contracting, labor practices (including the use of foreign labor), and infringements on national sovereignty have fueled public protests and led to project renegotiations or cancellations (Economy, 2018). This resistance has forced Beijing to adapt its messaging and practices, emphasizing concepts like "consultation and cooperation for shared benefits" and greater attention to local concerns and sustainability standards.

Similarly, Western efforts at democracy promotion and governance reform, often intended to fill normative or institutional vacuums, have encountered resistance not only from incumbent authoritarian regimes but also from segments of populations skeptical of external interference in domestic political affairs or the perceived imposition of foreign models. The "color revolutions" in several post-Soviet states, which were seen by Russia as Western-backed political vacuum-filling, generated intense counter-reactions from Moscow and like-minded regimes, leading to the development of sophisticated countermeasures against perceived Western political interference and "foreign agent" laws (Wilson, 2017; Ambrosio, 2009). The agency of local actors in mediating, resisting, or co-opting external influence is a critical factor often underestimated by intervening powers.

9.4. Normative and Legal Constraints

Prevailing international norms and legal frameworks, particularly those concerning state sovereignty, non-interference in internal affairs, and the right to self-determination, place increasing, albeit unevenly enforced, constraints on overt and coercive vacuum-filling operations (Finnemore & Sikkink, 1998; Reus-Smit, 2013). While these normative and legal frameworks are frequently contested and sometimes violated, they nevertheless tend to raise the legitimacy costs for powers perceived as acting in contravention of established international principles, potentially leading to diplomatic isolation, sanctions, or reputational damage.

Russia's annexation of Crimea in 2014, while arguably effective from Moscow's perspective in filling a perceived security vacuum following Ukraine's Euromaidan revolution and preventing NATO encroachment, triggered widespread international condemnation, non-recognition policies, and significant economic sanctions that imposed substantial long-term costs on the Russian economy (Allison, 2014; Charap & Colton, 2017).

Similarly, unilateral American interventions, such as the 2003 invasion of Iraq (which was not authorized by the UN Security Council), generated considerable normative backlash and international criticism, complicating subsequent U.S. influence operations and diminishing its "soft power" in certain regions. Increasingly, powers engaged in vacuum-filling feel compelled to frame their activities in terms consistent with international law and norms—emphasizing consent from host nations, partnership, mutual benefit, respect for sovereignty, and contributions to global or regional public goods—even when their underlying motivations may be driven by traditional power projection objectives. This normative environment constrains the available methods, or at least the public justification, of vacuum-filling behavior, pushing actors towards more indirect or ostensibly benign forms of influence.

9.5. Complexity, Unintended Consequences, and the Limits of Control

Perhaps the most fundamental and pervasive challenge to successful vacuum-filling policies stems from the inherent complexity of the target societies and geopolitical environments, and the frequent emergence of unforeseen and often counterproductive unintended consequences (Scott, 1998; Jervis, 1997). External powers typically possess incomplete or flawed understandings of local socio-political dynamics, cultural nuances, historical grievances, and power structures. They often struggle to accurately anticipate how their interventions will interact with indigenous forces and complex local systems, leading to miscalculations and policy failures.

The U.S. experiences in Iraq and Afghanistan over two decades serve as stark reminders that even massive resource commitments and overwhelming military superiority cannot guarantee successful or sustainable vacuum-filling when confronting complex societal dynamics, resilient local resistance, and weak or illegitimate local partners (Dodge, 2013; Suhrke, 2013). Similarly, Russia's intervention in Syria, while achieving its core objectives of preserving the Assad regime and securing a Mediterranean military presence, has entangled Moscow in a protracted and costly conflict with an uncertain long-term endgame and significant humanitarian repercussions (Kozhanov, 2018).

Vacuum-filling operations frequently generate "blowback" effects that can undermine the initial objectives or create new problems. The Western intervention in Libya in 2011, which successfully removed the Gaddafi regime, inadvertently created a persistent governance vacuum and a failed state. This has drawn in multiple competing external powers, fueled a protracted civil war, generated significant refugee flows towards Europe, and allowed extremist groups to gain footholds, thereby destabilizing the wider Sahel region (Wehrey & Lacher, 2021).

These various challenges and limitations mean that vacuum-filling strategies rarely achieve all their stated objectives and often generate costs and complications that may outweigh the initially perceived benefits. The most prudent and potentially successful approaches tend to involve clearly defined and limited objectives, sustainable resource commitments, a deep understanding of and sensitivity to local dynamics, robust risk assessment, and the flexibility to adapt strategies as conditions evolve, rather than adhering to rigid grand designs.

10. The Future of Vacuum Politics in an Evolving International System

As the international system continues its complex and often turbulent evolution—characterized by shifts in relative power, the rise of new actors, technological disruption, and growing contestation over global norms—the dynamics of vacuum-filling are likely to undergo significant transformations. This section examines emerging trends and potential future trajectories for "vacuum politics" in this changing global order.

10.1. Proliferation of Power Vacuums in a Transitional and Fragmented Order

The ongoing transition from a period of U.S. unipolar preeminence towards a more multipolar or perhaps "multi-nodal" international system is likely to generate additional power vacuums across various geographic regions and functional domains (Kupchan, 2012; Bremmer, 2021). As established powers, including the United States and some European nations, reassess and potentially recalibrate their global commitments in response to domestic pressures, shifting strategic priorities, and evolving relative power dynamics, new spaces may open for aspiring global and regional powers to expand their influence (Acharya, 2017).

The Middle East has already been a prominent arena for this dynamic, with perceived American retrenchment or policy shifts creating opportunities for regional powers (e.g., Iran, Turkey, Saudi Arabia, UAE) and external actors (e.g., Russia, China) to assert new influence and reshape regional alignments (Lynch, 2015; Gause, 2020). Similar processes of competitive vacuum-filling may unfold or intensify in parts of Africa, Southeast Asia, Latin America, and even within specific sub-regions of Europe, should established security providers or economic partners reduce their engagement or shift their strategic focus.

Beyond traditional geographic regions, functional domains such as global technological governance (e.g., AI, quantum computing, biotechnology), international climate policy implementation, global health security architecture, and the governance of outer space and cyber space may experience significant leadership and regulatory vacuums. This occurs as existing international institutional arrangements struggle to adapt to emerging challenges, great power consensus erodes, or dominant actors are unwilling or unable to provide necessary public goods (Patrick, 2014). The fragmentation of global governance creates opportunities for various state and non-state actors to establish influence in specialized niches where they possess capabilities, interests, or normative visions.

10.2. Increased Competition Among Multiple and Diverse Vacuum-Fillers

Unlike the Cold War period, where power vacuums typically triggered bipolar competition primarily between the two superpowers, contemporary and future vacuums often attract a more diverse array of competing actors with varying capabilities, motivations, and strategic approaches. This more complex and crowded competitive environment creates both novel constraints and new opportunities for those engaging in vacuum-filling, as well as for the states or regions experiencing the vacuum. In regions like the Middle East, Africa, and increasingly the Indo-Pacific, vacuums are drawing in not only global powers (U.S., China, Russia, EU) but also assertive regional powers (e.g., Turkey, Iran, Saudi Arabia, India, Japan, Australia), influential middle powers, former colonial powers seeking to retain relevance (e.g., France, UK), and a host of international organizations and non-state actors—all pursuing often divergent objectives through various instruments (Jones, 2019). This multiplicity of actors can limit any single power's ability to establish unchallenged hegemonic control, while simultaneously creating complex alliance possibilities, fluid balance-of-power dynamics, and opportunities for forum-shopping by local actors.

The involvement of multiple competing powers may, in some circumstances, paradoxically benefit target states or local actors within vacuum regions. It can provide them with greater leverage to play external actors against each other, diversify their partnerships, resist undue influence from any single power, and extract more favorable terms for cooperation or assistance (Verhoeven, 2020). Ethiopia, for example, has historically attempted to balance relationships with the United States, China, Gulf states, and European powers to maintain a degree of autonomy while securing external support for its development and security objectives, though this balancing act faces increasing challenges.

10.3. Technological Transformation of Vacuum Politics: New Tools, New Terrains

Emerging and rapidly advancing technologies are profoundly transforming both the methods and the targets of vacuum-filling strategies. Digital tools, AI-driven capabilities, advanced surveillance systems, and cyber operations provide new mechanisms for projecting influence, often with lower direct costs, greater deniability, and wider reach than traditional military or economic approaches (Nye, 2011; Lin, 2017). These capabilities allow powers to engage in informational warfare, shape narratives, influence political processes, and gather intelligence in ways that can fill or exploit perceived vacuums in information environments or governance structures. Simultaneously, new technological domains themselves are becoming critical targets for vacuum-filling as powers compete to establish technical standards, control critical infrastructure, shape governance frameworks, and achieve dominance in foundational technologies of the future. The ongoing global competition to shape the development and deployment of artificial intelligence, quantum computing, 5G/6G telecommunications, biotechnology, and commercial space activities represents a form of vacuum-filling in domains that currently lack established global regulatory frameworks or clearly dominant players (Segal, 2020). Establishing early leadership in these areas can confer significant long-term economic, strategic, and normative advantages.

Digital connectivity, while offering immense benefits, also creates new vulnerabilities to externally influence operations and cyber-attacks, potentially exacerbating existing societal cleavages or undermining trust in institutions. Conversely, it can also empower local resistance movements, civil society organizations, and investigative journalists to monitor, expose, and challenge external vacuum-filling operations or malign influence campaigns (Diamond, 2019).

10.4. The Expanding Role of Non-State Actors in Vacuum Politics

The growing influence and agency of a diverse array of non-state actors—including multinational corporations (especially large technology companies), private military and security companies (PMSCs), international non-governmental organizations (INGOs), philanthropic foundations, transnational criminal organizations, and religious or ideological movements—adds further complexity to contemporary vacuum politics (Cooley & Nexon, 2020; Avant et al., 2022). These entities increasingly operate alongside, in partnership with, or sometimes in opposition to states in filling governance, security, economic, and service provision vacuums, often with substantial operational independence and their own distinct agendas.

Global technology companies like Google, Meta (Facebook), Amazon, Microsoft, and Huawei are increasingly functioning as de facto governance actors in digital spaces. They establish and enforce rules for information flows, content moderation, data privacy, and cybersecurity that may align with, supplement, or contradict state preferences and regulations, thereby filling regulatory vacuums in the digital realm (DeNardis, 2014; Zuboff, 2019). Private military companies, such as Russia's Wagner Group or various Western PMSCs, enable more deniable, flexible, and sometimes cost-effective power projection or security provision, particularly in fragile states or conflict zones in regions like Africa and the Middle East, where direct state military intervention might be politically untenable or too costly (Marten, 2019; Spearin, 2017).

Philanthropic organizations (e.g., the Gates Foundation) and large INGOs (e.g., Médecins Sans Frontières) similarly fill critical governance and service provision vacuums in areas like global health, humanitarian aid, environmental protection, and development assistance. While often providing essential public goods, their activities can also reflect normative agendas and may sometimes be complicated or align with traditional state-led vacuum-filling strategies (Hall, 2015; Barnett & Finnemore, 2004).

10.5. Intensifying Domestic Constraints on Vacuum-Filling Ambitions

Growing domestic political constraints, economic pressures, and shifting public opinion may increasingly limit the ability and willingness of states, particularly established democratic powers, to sustain ambitious, costly, or risky vacuum-filling operations abroad. Public skepticism towards foreign interventions, "endless wars," and extensive overseas commitments has risen in many traditional vacuum-filling powers, including the United States and several European nations, creating political barriers to expensive or protracted engagements (Walt, 2018). Economic pressures, exacerbated by factors such as the COVID-19 pandemic, rising inflation, climate change adaptation costs, and domestic social spending demands, further constrain the resources available for extensive foreign policy initiatives. Even a rising power like China has faced growing domestic scrutiny and questioning of the costs and benefits of its Belt and Road Initiative expenditures, particularly in the context of its own economic slowdown, leading to calls for more careful project selection, greater emphasis on commercial viability, and a focus on domestic priorities (Economy, 2018).

These domestic constraints may gradually incentivize a shift in vacuum-filling strategies towards lower-cost, lower-visibility, and more politically sustainable approaches. This could mean an increasing emphasis on economic, technological, and informational tools over large-scale military deployments; working through multilateral frameworks or partnerships rather than pursuing unilateral interventions; and focusing more selectively on core strategic priorities rather than attempting comprehensive regional dominance or nation-building.

10.6. The Potential for Cooperative Approaches to Managing Global Vacuums

While competitive vacuum-filling will undoubtedly remain a prominent feature of international relations, there may also be an increasing recognition among states that certain types of vacuums—particularly those related to transnational threats and challenges—pose risks to shared interests and may require cooperative or collective management rather than zero-sum competition. Global challenges such as pandemic diseases, climate change impacts, transnational terrorism, cyber insecurity, financial instability, and unregulated emerging technologies create functional governance vacuums that no single power can effectively fill or manage alone.

The COVID-19 pandemic starkly illustrated both the dangers of leadership and coordination vacuums in global health governance and, albeit imperfectly, spurred some tentative moves towards more cooperative international approaches to vaccine development, distribution, and pandemic preparedness (Nichols, 2020). Similar dynamics, driven by necessity and shared vulnerability, may emerge in other domains where unilateral or competitive approaches prove manifestly inadequate for addressing complex transnational challenges that transcend borders and ideologies.

Regional organizations (e.g., ASEAN, African Union, European Union) may increasingly serve as vehicles for collaborative vacuum-filling or, more accurately, for managing power transitions and regional order through institutionalized frameworks that aim to constrain unilateral actions and foster burden-sharing. ASEAN's role in attempting to manage great power competition in Southeast Asia and maintain regional stability, despite its inherent limitations and adherence to principles of non-interference, offers a potential, if imperfect, model for more cooperative approaches to regional order during periods of power transition and heightened vacuum-filling activity (Acharya, 2014; Ba, 2016).

The future of vacuum politics will likely be characterized by complex and often contradictory mixtures of intensified competition and pragmatic cooperation. Different domains and regions may exhibit varying balances, depending on the perceived zero-sum nature of the interests involved, the severity of shared threats, and the availability of effective multilateral mechanisms. While military security and direct geopolitical influence may remain primarily competitive arenas, functional domains concerning global public goods, transnational risks, and shared technological governance may see a greater, though still contested, push towards more cooperative approaches to filling critical leadership and regulatory vacuums.

11. Discussion

The comprehensive review of literature underscores that the phenomenon of "power vacuums" and the ensuing strategic maneuvers to fill them are not merely historical footnotes but enduring and evolving dynamics central to international relations (Gilpin, 1981; Acharya, 2014). The analysis reveals a consistent pattern, from ancient empires to contemporary geopolitical landscapes, where the decline or withdrawal of established powers invariably creates opportunities and perceived threats that motivate other actors to expand their influence (Heather, 2007; Fromkin, 1989; Modelski & Thompson, 2011).

Key findings indicate that while the fundamental impulse to fill vacuums persists, its manifestations, strategies, and the actors involved have grown increasingly complex and multidimensional. A significant implication of these findings is the heightened potential for strategic competition and instability in the current transitioning international system, often characterized as moving towards multipolarity (Allison, 2017; Mearsheimer, 2019). The assertive rise of powers like China and the resurgence of Russia, coupled with the evolving role of the United States and influential regional actors, have cultivated a fertile ground for intensified vacuum-filling competition across diverse domains—military, political, economic, cultural, and critically, technological (Cooley & Nexon, 2020; Haass, 2017; Hillman, 2021). This necessitates a shift in analytical focus from purely military-centric views of power projection to understanding sophisticated "smart power" strategies that blend various instruments of influence (Melissen & Sarti, 2021). The increasing importance of economic statecraft, exemplified by China's Belt and Road Initiative (Chatzky & McBride, 2020), and the contestation in technological spheres like 5G and AI governance (Segal, 2020), highlight new arenas where vacuums are identified and contested.

This literature also brings to light several gaps and limitations in current understanding. While extensive research exists on the actions of major powers, the agency of local actors within these "vacuum" regions—their capacity to resist, mediate, or co-opt external influences—often remains underexplored (Acharya, 2014). Furthermore, the long-term consequences of various vacuum-filling strategies, particularly those employing economic or technological leverage, require more systematic longitudinal analysis beyond immediate geopolitical gains (Hillman, 2019). The normative and ethical dimensions of interventions aimed at filling vacuums, especially concerning sovereignty and local self-determination, also warrant deeper scrutiny (Finnemore & Sikkink, 1998). Moreover, while the document outlines different theoretical perspectives (Waltz, 1979; Keohane, 1984; Wendt, 1999), the practical interplay and potential synthesis of these frameworks in explaining complex contemporary cases could be further developed.

The challenges inherent in vacuum-filling policies—ranging from security dilemmas and economic overextension (Jervis, 1978; Kennedy, 1987) to legitimacy issues and the sheer complexity of local contexts (Scott, 1998)—suggest that the efficacy of such strategies is often constrained. Domestic political landscapes, finite resource availability, and the intricate interdependence of the global order further temper the ambitions of vacuum-filling states (Kupchan, 2012). These points towards a future where successful influence projection may depend less on unilateral dominance and more on adaptive, sustainable, and potentially cooperative approaches, especially in addressing transnational challenges that create functional governance vacuums (Patrick, 2014). Future research, as outlined in the subsequent section, should delve into these nuanced areas to provide a more holistic understanding of this critical international dynamic.

12. Recommendations for Further Research

Based on the comprehensive analysis of vacuum-filling dynamics, their evolving nature, and inherent complexities, the following recommendations are proposed for policymakers and researchers:

For Policymakers:

• Adopt Adaptive "Smart Power" Strategies: Policymakers should develop and implement comprehensive "smart power" strategies that integrate diplomatic, economic, technological, cultural, and informational tools, rather than relying predominantly on military force, when addressing power vacuums. This reflects the observed evolution towards multidimensional approaches to influence (Melissen & Sarti, 2021; Shambaugh, 2013).
• Conduct Rigorous Risk Assessments: Before engaging in vacuum-filling activities, undertake thorough risk assessments that meticulously evaluate potential security dilemmas (Jervis, 1978), risks of economic overextension (Kennedy, 1987), the likelihood of local resistance, and the possibility of unintended negative consequences (Scott, 1998).
• Prioritize Contextual Understanding and Local Agency: Invest in developing a deep understanding of local socio-political dynamics, cultural specificities, and historical contexts. Critically, acknowledge and incorporate the agency of local actors in policy formulation to enhance the legitimacy, effectiveness, and sustainability of any engagement (Acharya, 2014).
• Foster International Cooperation for Transnational Challenges: Actively pursue and strengthen international cooperation through multilateral frameworks to manage functional governance vacuums arising from transnational threats such as climate change, pandemics, and cyber insecurity, where unilateral vacuum-filling is often ineffective or counterproductive (Patrick, 2014).
• Promote Sustainable and Mutually Beneficial Engagement: Emphasize long-term, sustainable engagement, particularly in economic and technological partnerships, that prioritize mutual benefit, transparency, and local development needs. This approach is more likely to build resilient and positive relationships compared to strategies that risk creating unsustainable dependencies or fostering resentment (cf. Hillman, 2019; Bräutigam, 2020).

For Researchers:

• Investigate Long-Term Impacts of Contemporary Strategies: Conduct further in-depth, comparative, and longitudinal case studies on the long-term stability implications and socio-economic consequences of contemporary vacuum-filling strategies, particularly those employing economic instruments (e.g., Belt and Road Initiative) and technological leverage (e.g., Digital Silk Road, 5G rollout) (Hillman, 2021; Chatzky & McBride, 2020).
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• Deepen Analysis of Local Agency: Expand research into the agency of local actors and societies within regions perceived as power vacuums. Examine their diverse strategies of resistance, adaptation, mediation, and co-optation of external influences, moving beyond a purely great-power-centric view (Acharya, 2014).
• Scrutinize Normative and Ethical Dimensions: Undertake more rigorous investigation of the normative and ethical dimensions of vacuum-filling interventions, focusing on issues of sovereignty, the responsibility to protect, self-determination, and the accountability of intervening powers (Finnemore & Sikkink, 1998; Reus-Smit, 2013).
• Develop Integrated Theoretical Frameworks: Work towards developing and empirically testing more integrated theoretical frameworks that can holistically explain the complex interplay of material power, institutional variables, ideational factors (constructivism), domestic political dynamics, and individual leadership in shaping contemporary vacuum-filling behavior and outcomes.
• Analyze the Evolving Role of Non-State Actors: Examine the increasingly significant role and impact of diverse non-state actors—including multinational technology corporations, private military and security companies, international non-governmental organizations, and transnational movements—in shaping, contesting, and filling power vacuums across various domains (Cooley & Nexon, 2020; Avant et al., 2022).
• Explore Cooperative Vacuum Management: Investigate the conditions under which cooperative or collective management of power vacuums, particularly functional ones, becomes feasible and effective, and identify best practices for such multilateral approaches (Acharya, 2014; Patrick, 2014).