Executive Summary:

The conflict between India and Pakistan over the region of Kashmir has endured for over seven decades, originating from the tumultuous partition of British India in 1947.

This protracted dispute, rooted in competing claims and national identities, took on a perilous new dimension in 1998 when both nations openly declared their nuclear weapons capabilities. The possession of nuclear arsenals has elevated the stakes of any confrontation, transforming a regional territorial dispute into a potential global security crisis. Recent escalations, exemplified by the deadly attack on tourists in Pahalgam in April 2025, underscore the persistent volatility of the relationship and the ever-present risk of conflict

This report analyses the historical context, current dynamics, nuclear capabilities, potential escalation scenarios, and consequences of a nuclear conflict arising from the India-Pakistan dispute over Kashmir.

Introduction:

The Kashmir conflict stands as one of the most protracted and complex international disputes, casting a long shadow over South Asia since the independence and partition of India in 1947. The disagreement over the status of this picturesque Himalayan region has been a constant source of animosity between India and Pakistan, leading to multiple wars and countless skirmishes. The acquisition of nuclear weapons by both nations in 1998 marked a critical juncture, introducing a layer of strategic complexity and dramatically increasing the potential consequences of any future conflict. Nuclear deterrence now underpins the strategic calculations of both New Delhi and Islamabad, influencing their responses to regional crises. The recent surge in tensions following the brutal attack on tourists in Pahalgam in April 2025 has once again brought the region to the brink, raising alarm within the international community about the possibility of armed conflict between two nuclear-armed neighbours.

This report aims to provide a comprehensive analysis of the nuclear threat stemming from the enduring India-Pakistan conflict over Kashmir, examining the likelihood and potential ramifications of nuclear escalation.

Historical Roots of the Kashmir Conflict:

The genesis of the Kashmir conflict lies in the partition of British India in August 1947, which created the independent nations of India and Pakistan.2 The partition, based on religious demographics, did not neatly accommodate the princely states, granting them the choice to accede to either dominion or remain independent. Jammu and Kashmir, a princely state with a Muslim-majority population ruled by a Hindu Maharaja, Hari Singh, initially chose to remain independent.

However, this decision was short-lived. In October 1947, facing a rebellion in the western districts and an invasion by Pakistani tribal militias, Maharaja Hari Singh appealed to India for military assistance.2 In exchange for this aid, he signed the Instrument of Accession to India.1 India accepted the accession, contingent upon a future plebiscite to determine the will of the Kashmiri people. India subsequently referred the matter to the United Nations in January 1948.

The conflict over Kashmir has since escalated into several major wars between India and Pakistan. The first Indo-Pakistani War (1947-1948) ended with a UN-mediated ceasefire, establishing a ceasefire line that later became the Line of Control (LoC).1 This war resulted in the division of Kashmir, with India gaining control of approximately two-thirds of the state, including the Kashmir Valley, Jammu, and Ladakh, while Pakistan controlled roughly a third, known as Azad Kashmir and Gilgit-Baltistan. The second Indo-Pakistani War in 1965 was triggered by Pakistan’s Operation Gibraltar, an attempt to infiltrate forces into Indian-administered Kashmir to incite an uprising. This war ended in a stalemate following international intervention.23 In 1999, a limited conflict erupted in the Kargil region when Pakistani soldiers and insurgents crossed the LoC.  This conflict, even after both nations possessed nuclear weapons, underscored the persistent risk of military escalation and ended with a US-brokered withdrawal. Beyond these major wars, numerous armed skirmishes and periods of heightened tension, including the 1971 war which led to the creation of Bangladesh and impacted the dynamics in Kashmir, have characterised the relationship.

The ceasefire line established after the first war was formalised as the Line of Control (LoC) through the Simla Agreement in 1972. While the Simla Agreement aimed to resolve differences through bilateral negotiations, the underlying dispute over Kashmir remained unresolved, leaving the LoC as a highly militarised de facto border. Frequent exchanges of fire across this volatile boundary, even with a ceasefire agreement in place since 2021 34, highlight the continued risk of unintended escalation

The Current State of India-Pakistan Relations and Kashmir:

The relationship between India and Pakistan, particularly concerning Kashmir, remains fraught with tension, as evidenced by recent escalations. In April 2025, a deadly militant attack in Pahalgam, Indian-administered Kashmir, resulted in the killing of 26 tourists. This attack, one of the deadliest targeting civilians in recent years, triggered strong condemnation from India, which was quick to imply Pakistan’s involvement. While India did not immediately provide concrete evidence, this pattern of blaming Pakistan following attacks has become a recurring feature in their strained relationship.9 In response, Pakistan vehemently denied any role in the Pahalgam attack and offered to cooperate with a credible international probe.

The aftermath of the Pahalgam attack witnessed a rapid deterioration of diplomatic ties between the two nuclear-armed neighbours. Both countries engaged in tit-for-tat measures, including downgrading diplomatic relations, expelling each other’s diplomats, and closing key land border crossings.2 These actions marked a new low in their already frigid relationship. Further escalating the situation, India announced the suspension of its participation in the Indus Waters Treaty, a crucial water-sharing agreement that had remarkably survived previous wars. Pakistan responded by threatening to withdraw from the Simla Agreement, a cornerstone of their bilateral relations that established the LoC.

In addition to these diplomatic manoeuvres, military posturing along the Line of Control intensified. Reports emerged of gunfire exchanges between Indian and Pakistani troops in the days following the Pahalgam attack. Pakistan also test-fired a ballistic missile, the Abdali Weapon System, amid the heightened tensions, a move seen as a demonstration of its military readiness. Reports also indicated increased military activity and troop movements on both sides of the border.

Nuclear Capabilities of India and Pakistan: A Comparative Analysis:

India and Pakistan, both nuclear-armed states, possess arsenals of comparable size. Estimates suggest that India has approximately 172 nuclear warheads, while Pakistan holds around 170.7 India is in the process of developing a nuclear triad, with delivery systems including land-based ballistic missiles like the Agni series, nuclear-capable aircraft such as the Mirage 2000 and Rafale, and sea-based capabilities with the Dhanush and K-15 submarine-launched ballistic missiles (SLBMs).7 India’s focus appears to be expanding beyond Pakistan, with the development of longer-range missiles capable of reaching targets in China.47 Pakistan’s nuclear arsenal includes land-based missiles such as the Abdali, Ghaznavi, Shaheen series, Ghauri, and Nasr, as well as nuclear-capable aircraft like the Mirage III/V and potentially the JF-17.52 Pakistan is also developing sea-based capabilities with the Babur-3 submarine-launched cruise missile (SLCM) 80 and has emphasised the development of tactical nuclear weapons like the Nasr, intended for battlefield use against India’s larger conventional forces. Both nations are also reportedly developing Multiple Independently Targetable Re-entry Vehicles (MIRVs).55

India has a declared “No First Use” (NFU) policy, stating that it will only use nuclear weapons in retaliation against a nuclear attack on Indian territory or forces. However, this policy has been subject to debate and potential reconsideration. In contrast, Pakistan adheres to a doctrine of “Full Spectrum Deterrence,” which includes the possibility of first use in response to a perceived existential threat or to counter large-scale conventional military attacks from India. This difference in declared doctrines highlights the asymmetry in their strategic postures.

Organisations like the Stockholm International Peace Research Institute (SIPRI) provide annual assessments of global nuclear arsenals. Their data indicates a slight edge for India in the number of warheads in recent years , although estimates vary. SIPRI also notes the ongoing modernisation of nuclear forces by both countries. The Federation of American Scientists (FAS) through its Nuclear Notebooks offers detailed analyses, highlighting the continuous development of new delivery systems and warhead technologies by both India and Pakistan. Both organisations underscore the lack of official transparency from both governments regarding the precise size and composition of their nuclear arsenals.

Assessing the Nuclear Threat: Likelihood and Scenarios of Escalation:

Expert opinions on the likelihood of nuclear conflict between India and Pakistan in the context of the Kashmir dispute vary. Some analysts, like US political scientist John Mearsheimer, have expressed serious concerns, warning of a “real potential for nuclear use” due to the conventional military imbalance favouring India, which could compel Pakistan to resort to nuclear weapons if facing a significant defeat. Mearsheimer also noted the reduced US intervention in the current crisis compared to previous standoffs, potentially increasing the risk of escalation. In contrast, other experts believe that nuclear deterrence will likely hold, preventing a major war, but they also emphasise the persistent danger of miscalculation or misinterpretation, especially given the absence of robust crisis management mechanisms.34 The history of close calls between India and Pakistan underscores the fragility of this deterrence. Notably, historical US intelligence assessments from the 1980s and 90s also highlighted a significant risk of conventional conflict escalating to a nuclear exchange between the two nations.

Several potential triggers could lead to nuclear escalation in the India-Pakistan context. A major terrorist attack in Kashmir or mainland India, attributed to Pakistan-backed groups, could create immense domestic pressure on India to retaliate forcefully, potentially leading to actions that Pakistan might perceive as an existential threat.2 A large-scale conventional military setback for Pakistan could also trigger nuclear escalation. Given Pakistan’s “Full Spectrum Deterrence” doctrine, which emphasises the use of tactical nuclear weapons to counter India’s conventional superiority, a significant conventional defeat might prompt Pakistan to consider this option.7 Furthermore, the persistent lack of trust and effective communication channels between the two countries significantly increases the risk of miscalculation or misinterpretation of military movements, intentions, or signals during periods of heightened tension.

Plausible scenarios of nuclear conflict include the use of tactical nuclear weapons by Pakistan in response to a perceived imminent conventional defeat. This could then lead to retaliatory nuclear strikes by India, potentially escalating rapidly from tactical to strategic weapons. Another scenario involves a conventional conflict spiralling out of control, with either side perceiving a risk of decisive loss, leading to the use of strategic nuclear weapons against high-value targets.

Consequences of a Nuclear Conflict in South Asia:

The humanitarian impact of a nuclear conflict between India and Pakistan would be catastrophic. Estimates suggest that a nuclear exchange could result in the immediate deaths of millions, potentially ranging from 50 to 125 million people, depending on the scale and yield of the weapons used. The densely populated nature of the subcontinent would exacerbate the casualty figures. Beyond the immediate deaths, a nuclear conflict would lead to mass displacement, widespread injuries, and long-term health effects due to radiation exposure. The already strained healthcare infrastructure in both countries would be quickly overwhelmed.

The environmental ramifications of a nuclear war in South Asia extend beyond the immediate region. Studies indicate a significant risk of nuclear winter, caused by the injection of massive amounts of black carbon into the upper atmosphere from nuclear detonations and the resulting firestorms. This could lead to a substantial drop in global temperatures and altered precipitation patterns for years. The impact on agriculture and ocean ecosystems would be devastating, potentially leading to global food shortages and famine. Plant growth could decrease significantly, and ocean productivity would likely plummet.

The economic and geopolitical repercussions of a nuclear conflict in South Asia would be severe. Both India and Pakistan would suffer devastating economic losses due to the destruction of infrastructure and the disruption of trade and economic activity. The conflict would also lead to significant regional destabilisation and have profound implications for global geopolitics. A nuclear exchange between two states would set a dangerous precedent and could undermine the international non-proliferation regime, potentially encouraging other nations to pursue nuclear weapons.

8. Diplomatic Efforts, De-escalation Measures, and Confidence Building:

The Kashmir conflict has been a subject of diplomatic initiatives since its inception. The United Nations played an early role, passing numerous resolutions on the issue. However, a mutually acceptable resolution has remained elusive due to the differing positions of India and Pakistan. While Pakistan has often sought international intervention, India has largely maintained that the Kashmir issue is a bilateral matter to be resolved through direct talks. The Simla Agreement of 1972 established the Line of Control and emphasised bilateral negotiations as the way forward. However, this framework has not led to a final settlement, and Pakistan’s recent threat to withdraw from the agreement highlights the ongoing tensions. In the aftermath of the Pahalgam attack, several countries, including Iran and the United States, have offered to mediate or urged de-escalation.

Over the years, India and Pakistan have implemented various Confidence Building Measures (CBMs) aimed at promoting trust and reducing tensions. These include political, military, economic, and people-to-people initiatives. A significant military CBM is the agreement on not attacking each other’s nuclear facilities, which has been maintained despite overall strained relations. However, the effectiveness of these CBMs has often been limited due to inconsistent implementation and the reversibility of many measures during periods of high tension.

De-escalation strategies hinge on the resumption of sustained dialogue between India and Pakistan at multiple levels. While India has been hesitant to accept third-party mediation on Kashmir, the current crisis has seen renewed calls for international involvement. Specific de-escalation measures could include restoring all communication channels, reaffirming commitment to existing CBMs, and avoiding any further provocative actions or rhetoric.

Nuclear Deterrence Stability in South Asia: Challenges and Perspectives:

The concept of the stability-instability paradox is particularly relevant in the context of nuclear deterrence between India and Pakistan. While the presence of nuclear weapons may have deterred large-scale conventional wars, it has not prevented limited conventional conflicts or proxy wars below the nuclear threshold.

Evolving military technologies pose new challenges to nuclear deterrence stability in South Asia. The development of cyber warfare capabilities introduces the risk of attacks on critical infrastructure, including nuclear command and control systems.98 The difficulty in attributing cyberattacks further complicates the security landscape. India’s pursuit of missile defence systems could be perceived by Pakistan as an attempt to gain a first-strike advantage, potentially leading to a counter-buildup of offensive capabilities, such as MIRVs.69 The development of sea-based nuclear capabilities by both nations also introduces new ambiguities and complexities in strategic calculations at sea.

There are differing viewpoints on the long-term stability of nuclear deterrence in South Asia. Some experts hold an optimistic view, arguing that the catastrophic consequences of nuclear war will continue to deter large-scale conflict. Others maintain a pessimistic outlook, citing the inherent instability in the relationship, the risk of accidents and miscalculations, and the potential for escalation, making nuclear conflict a persistent and dangerous threat.

Conclusion and Recommendations:

The India-Pakistan conflict over Kashmir remains a deeply entrenched and highly complex issue with a significant nuclear dimension. The recent escalation following the Pahalgam attack underscores the persistent volatility of the relationship and the ever-present danger of military confrontation. The possession of nuclear weapons by both nations has raised the stakes dramatically, creating a scenario where any large-scale conflict carries the risk of catastrophic escalation. While nuclear deterrence has arguably prevented full-scale wars, it has not eliminated the possibility of limited conflicts or proxy wars, and the risk of miscalculation or unintended escalation remains alarmingly high. The potential humanitarian, environmental, and geopolitical consequences of a nuclear conflict in South Asia are immense and would extend far beyond the immediate region. Therefore, addressing this enduring conflict and mitigating the nuclear threat requires sustained and concerted efforts from both India and Pakistan, as well as the active engagement of the international community.

To mitigate the nuclear threat and foster a peaceful resolution to the Kashmir conflict, the following recommendations are proposed:

For India and Pakistan:

• Re-establish and consistently maintain open channels of communication at all levels, including political, diplomatic, and military, to prevent misunderstandings and manage crises effectively.
• Reaffirm and strengthen existing Confidence Building Measures (CBMs), ensuring their consistent implementation and exploring new measures to enhance transparency and trust.
• Exercise utmost restraint in public rhetoric and military posturing, particularly in the aftermath of escalatory events.
• Seriously consider the establishment of institutionalised Nuclear Risk Reduction Center’s (NRRCs) to facilitate real-time communication and de-escalation during crises.
• Re-engage in meaningful dialogue to explore all possible peaceful mechanisms for resolving the Kashmir dispute, taking into account the aspirations of the Kashmiri people

For the International Community:

• Maintain consistent diplomatic pressure on India and Pakistan to de-escalate tensions and prioritise dialogue as the primary means of resolving their disputes.
• Offer impartial mediation and active support for bilateral negotiations if requested by both India and Pakistan, respecting their sovereignty and territorial integrity.
• Promote greater transparency regarding nuclear arsenals in the region through international engagement and verification efforts.
• Support and encourage initiatives that foster people-to-people contact, cultural exchanges, and economic cooperation between India and Pakistan to build trust at the societal level.
• Continuously highlight the potentially devastating global consequences of a nuclear conflict in South Asia to maintain international focus and urgency on de-escalation and peaceful resolution.