Regional Security Complexes – South Asia 2024-2025

Regional Security Complexes – South Asia 2024-2025

by Mihajlo Botić

Introduction

South Asia has long been regarded as one of the most volatile regions in the international system. Encompassing India, Pakistan, Bangladesh, Nepal, Sri Lanka, the Maldives, and Afghanistan, the region is marked by intense security interdependence, historical enmities, and overlapping external influences. The enduring rivalry between India and Pakistan, combined with Afghanistan’s chronic instability and the fragility of smaller states, has created a regional environment in which security dynamics are more tightly bound within South Asia than across its borders. This is precisely why South Asia was a foundational case study around which regional security complex theory was first developed (Buzan and Wæver, 2003).

RSCT conceptualises regions as security complexes when patterns of amity and enmity, coupled with geographical proximity, generate sustained interdependence of security concerns. South Asia epitomises this logic: the India-Pakistan rivalry shapes nearly every aspect of the region’s security agenda, while other states either orbit around this axis or serve as insulators and buffers. The nuclearisation of the subcontinent, persistent terrorism, and the penetration of great powers such as the United States, China, and Russia heighten the stakes.

The guiding question in this Regional Security Monitor analysis is how South Asia’s Regional Security Complex (RSC) has evolved in 2024/2025. Has the structure remained largely stable, with India and Pakistan at its core, or are new dynamics – such as drone warfare, climate insecurity, and intensified Chinese influence – gradually transforming the logic of the complex? By applying RSCT, the analysis highlights both continuity and change, and explores possible future trajectories for the region.

Applying RSCT to South Asia

The historical legacy of South Asia’s security complex is rooted in the partition of British India in 1947, which created India and Pakistan amid mass violence and contested borders. The unresolved dispute over Kashmir institutionalised enmity between the two new states and made territorial integrity and national identity existential referent objects (Buzan and Wæver, 2003). Multiple wars (1947/48, 1965, 1971, 1999, 2025) reinforced the centrality of this rivalry, while the nuclearisation of both countries in 1998 further locked the region into a hostile, highly militarised security logic (Kapur, 2007).

Afghanistan has long functioned as a subcomplex within this regional environment (Buzan and Wæver, 2003; Acharya, 2007). Historically a buffer in the “Great Game” between the British and Russian empires, it became a site of overlay during the Soviet invasion in 1979 and the subsequent US-led intervention after 2001. Even after the withdrawal of NATO forces in 2021, Afghanistan remains a locus of insecurity, with the Taliban regime presiding over economic collapse, humanitarian crises, and renewed terrorist activity. Its instability spills over into Pakistan and affects the broader South Asian RSC. Afghanistan historically served as a buffer zone between rival imperial powers and continues to function as a buffer between South and Central Asia, while Iran and Myanmar can be considered insulators, separating South Asia from the Middle East and Southeast Asia, respectively (Buzan and Wæver, 2003). Nepal occupies a strategic position, playing a mixed role of insulator/buffer between the two regional complexes.

The principal actors are therefore India, Pakistan, and Afghanistan, with smaller states like Bangladesh, Nepal, Sri Lanka, and the Maldives playing secondary roles. India, with a population of approximately 1.4 billion and one of the world’s largest economies, with a GDP of around 3.9 trillion USD, functions as the regional hegemon, possessing overwhelming material capabilities and increasingly aligning with global actors such as the United States and Japan under the Indo-Pacific framework (World Bank, 2024). Pakistan, which has a population of nearly 250 million and a GDP of around 400 billion USD, counters India by leaning on its “all-weather” partnership with China, while simultaneously struggling with internal fragilities such as terrorism and economic crises (World Bank, 2024). Afghanistan, though weaker, constitutes a subcomplex because of its capacity to destabilise the neighbourhood and to invite external penetration (Buzan and Wæver, 2003).

The essential structure of South Asia fits neatly into RSCT’s model of a “standard” RSC (Buzan and Wæver, 2003). It is anarchic, with multiple autonomous units competing for survival. Power distribution is asymmetrical: India dominates, but its superiority is checked by Pakistan’s nuclear arsenal and China’s backing – a dynamic widely discussed in nuclear deterrence literature and analyses of Indo-Pakistani and Sino-South Asian strategic competition (Kapur 2007; Small 2015). Patterns of amity and enmity are stark, especially the entrenched hostility between India and Pakistan, as seen in recurring crises, fragile cooperation between India and Bangladesh, and mixed relations between India and Sri Lanka that oscillate between cooperation and competition in economic and security domains (Mohan, 2018). Processes of securitisation reinforce these structures, as political elites consistently portray the other side as existential threats, which is confirmed through analysis of discourses in South Asian political contexts (Rana, 2021). Together, these features establish South Asia as one of the most archetypal hostile security complexes described in Buzan and Wæver’s framework.

Regional Security Dynamics in 2024-2025

Events in the past two years illustrate both continuity and new developments in the South Asian RSC. The India-Pakistan rivalry remains the central axis, but it has manifested in novel ways that reveal evolving security practices.

In April 2025, the Pahalgam terrorist attack in Jammu and Kashmir killed 26 Indian civilians. New Delhi accused Pakistan-based groups of orchestrating the assault and launched Operation Sindoor, striking nine suspected militant facilities across the Line of Control and within Pakistan-administered Kashmir (India Times, 2025). This marked a significant escalation, as it was one of the first overt cross-border operations of such scale between two nuclear-armed neighbours in decades (India Times, 2025). Pakistani Prime Minister Shehbaz Sharif condemned the strikes and warned of retaliation, raising fears of uncontrolled escalation. Although U.S. and Chinese diplomatic interventions helped prevent further military exchanges, the crisis underscored how terrorism continues to function as a trigger for state-to-state conflict, sustaining the hostile logic of the RSC (Yusuf, 2025).

A parallel development has been the rapid militarisation of drone technologies. The India-Pakistan “drone battles” of mid-2025 marked the region’s entry into a new arms race (Reuters, 2025a). India has tripled its spending on unmanned aerial vehicles (UAVs), now investing around 470 million dollars, while Pakistan has sought Chinese and Turkish assistance to develop its own drone capabilities (Reuters, 2025b). Drone warfare not only intensifies the arms competition but also lowers the threshold for cross-border engagements, as unmanned platforms reduce the risks of escalation compared to manned incursions. Yet paradoxically, they may make conflict more frequent, embedding technological rivalry into the existing security complex.

Domestic instability in Pakistan has further complicated the regional picture. In September 2025, a suicide bombing in Quetta, Balochistan, killed at least 13 people at a political rally (AP News, 2025). Days later, militants attacked a security base in Bannu near the Afghan border, killing six personnel (Reuters, 2025d). These incidents illustrate Pakistan’s enduring struggle with terrorism and insurgency, which not only undermines internal security but also provides India with rhetorical ammunition to delegitimise Islamabad internationally. At the same time, the Pakistani state has securitised these attacks by accusing external actors, including India, of covert involvement, thereby reinforcing enmity patterns.

Another emerging dimension is climate and humanitarian insecurity. In August 2025, torrential monsoon rains forced Pakistan to release excess water from its dams, causing cross-border flooding into Indian Punjab. Over one million people were displaced on the Pakistani side, while Indian authorities accused Islamabad of mismanagement (Reuters, 2025b). Although not a military issue, the securitisation of water and climate events reflects the broadening of the security agenda in South Asia (Sultana and Scheffran, 2025). In Bangladesh, rising sea levels and cyclone risks are increasingly discussed in security terms, further demonstrating how RSCT’s notion of referent objects extends beyond traditional state-centric concerns (Monzur, 2013; Sultana et al., 2024).

Overall, the dynamics of 2024/2025 confirm that South Asia remains an anarchic, hostile RSC dominated by India-Pakistan antagonism, yet perceptions of security vary significantly among key actors, with Indian strategic discourse emphasising external threats and modernisation, while Pakistani narratives highlighting existential vulnerabilities (Maalik and Khokhar, 2025; Josukutty and Reem, 2025). Studies on public and elite perceptions of security in South Asia further show that states interpret threat differently – for example, Indian strategic thought often frames China as a major long‑term threat, while Pakistani discourses prioritize India as the immediate existential adversary, underscoring how security rhetoric and practice interact in shaping state behavior (Maalik and Khokhar, 2025; Josukutty and Reem, 2025). Yet the addition of drones, persistent terrorism, and climate insecurities demonstrates incremental transformation in this regional security complex. The essential anarchic structure remains constant, but these factors are reshaping threat management and strategic priorities. For example, drones lower the threshold for cross-border engagement, and climate-related crises expand the scope of what is considered a security concern. This incremental transformation indicates a broadening and deepening of the security agenda, rather than a fundamental structural change, pointing to evolving practices within a stable regional framework.

Interregional and Global Dynamics

South Asia’s RSC cannot be fully understood without considering its interactions with neighbouring complexes and great powers. Geographically, the region overlaps with Central Asia through Afghanistan, where instability spills into Pakistan and creates opportunities for global penetration. Afghanistan’s position as a subcomplex ensures that South Asia’s boundaries remain porous to influences from the Middle East and Central Asia.

Globally, external penetration remains pronounced. The United States, although having withdrawn militarily from Afghanistan, continues to act as a crisis manager, especially in the Pahalgam episode, where quiet U.S. mediation was critical to preventing escalation (Bhardwaj, 2025). Washington’s alignment with India under the Indo-Pacific strategy further embeds South Asia within wider geostrategic rivalries.

China’s role has grown significantly over the past decade, particularly through sustained investment since the establishment of the China-Pakistan Economic Corridor (CPEC) in 2015 and further consolidated around 2025 (CPEC Secretariat, 2025). Through the CPEC and military cooperation, Beijing provides Islamabad with economic aid and investment, including 8.5 billion dollars in new deals signed in 2025, along with diplomatic support and weapons supply (AP News, 2025b; Pakistan Today, 2025). In 2025, China also used the Shanghai Cooperation Organisation (SCO) as a platform to signal its partnership with India, with Xi Jinping and Narendra Modi declaring that the two countries should be “partners, not rivals” (Reuters, 2025). Yet beneath the rhetoric, competition persists along the Himalayan border, and China’s deepening ties with Pakistan complicate India’s security calculus.

Russia plays a secondary role but continues to supply arms to India and seeks balanced relations with Pakistan. Moscow remains one of India’s principal arms suppliers,  accounting for the majority of Indian defence imports over decades, while its exports to Pakistan have been substantially smaller, reflecting cautious engagement (Kapoor, 2024; Chatham House, 2024). Moscow’s outreach reflects its desire to maintain relevance in an increasingly China and United States-dominated environment.

The relative weights of security levels in South Asia are therefore clear: the regional level (India-Pakistan) remains dominant, but interregional and global levels heavily penetrate through Afghanistan, Chinese investment, and U.S. strategic partnerships. While Buzan and Wæver recognised the concept of overlay as external powers influencing regional complexes in their 2003 work, the scale and intensity of such overlay have grown in 2025, with political, economic, and strategic dimensions all playing a role. The complex illustrates RSCT’s concept of overlay, where external great powers significantly shape local dynamics, not only through direct military or diplomatic action, but also via investment and infrastructure projects.

Continuities, Changes, and Future Outlook

South Asia’s RSC is defined by profound continuity. The India-Pakistan rivalry, sustained by the unresolved Kashmir dispute, nuclear deterrence, and terrorism, remains the central axis of enmity. Afghanistan continues to function as a destabilising subcomplex, and regional institutions such as the South Asian Association for Regional Cooperation (SAARC) remain too weak to alter the logic of anarchy (Dash, 2008).

Yet recent developments also highlight important changes. The incorporation of drone warfare into military arsenals signals a technological and operational transformation, adding new layers of insecurity. The securitisation of climate change, as seen in cross-border flooding and migration debates, broadens the agenda beyond military threats. The intensification of Chinese involvement – economically through CPEC, diplomatically through SCO, and militarily through arms supplies – represents a significant situational and interregional shift, complicating rather than overturning India’s dominance.

Looking forward, three scenarios are plausible. The first is the continuation of the status quo, where India and Pakistan maintain a tense standoff punctuated by episodic crises such as Pahalgam. The second is further militarisation, with drones and other technologies escalating the arms race and increasing the frequency of low-intensity conflicts. The third, though less likely, is partial transformation, where cooperative responses to shared challenges such as climate change or trade might foster limited desecuritization. Given current trajectories, the status quo with episodic escalation remains the most likely outcome.

Conclusion

South Asia in 2025 exemplifies the enduring relevance of RSCT. The region remains one of the clearest illustrations of a hostile security complex, where historical enmities, nuclear deterrence, and terrorism bind states into a tightly interdependent security logic. The India-Pakistan rivalry continues to dominate, but the security agenda is evolving.

At the same time, external involvement has intensified primarily in the form of penetration rather than full overlay, as great powers increasingly shape (but do not replace) regional security interactions. While elements of overlay can be observed in specific domains and sub-regions, particularly through Chinese economic engagement, U.S. strategic partnerships, and developments in Afghanistan, these influences coexist with, rather than override, the local security complex. As a result, the security agenda is evolving: drone warfare, domestic insurgencies, and climate change are reshaping perceptions of threat, while global rivalries intersect with, but do not subsume, South Asia’s core regional dynamics (Buzan and Wæver 2003).

RSCT helps explain why these patterns persist – geography and history have created a structure that endures despite changes in leadership, technology, and external alignments. The essential features of South Asia’s RSC – anarchy, asymmetrical power distribution, entrenched enmity – remain intact, but incremental transformations suggest that the complex is not static. The interplay of continuity and change will define the region’s security trajectory in the years to come.

Ultimately, South Asia will continue to pose significant challenges to international security. Its nuclear dimension, susceptibility to terrorism, and vulnerability to climate change make it a region of global consequence. Understanding South Asia through the lens of RSCT not only clarifies its internal logic but also underscores why this region remains a focal point of global strategic concern.

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