Muhammad Ibrahim Nadeem
South Asia is one of the few regions where two rival nuclear powers remain divided by an unresolved territorial dispute and are frequently confronted by military standoffs. Time and again, whether triggered by a border incident, a terrorist attack, or a diplomatic crisis, Pakistan and India are pushed dangerously close to conflict. In such moments, discussions on deterrence inevitably resurface.
However, public debates often focus narrowly on numbers, how many nuclear warheads each country possesses, the range of their missiles, and the size of their delivery systems. While these factors are significant, they overlook a more fundamental principle. Strategic stability is determined not by the size of a nuclear arsenal but by the assurance that each state can survive a first strike and retaliate with devastating effect. This concept, known as assured second-strike capability, deserves far greater attention than simple comparisons of nuclear inventories.
Second-strike capability refers to a state’s ability to launch a nuclear retaliation even after absorbing a surprise attack intended to destroy its nuclear forces. At its core, it is a question of survivability rather than numerical strength. A country may possess hundreds of nuclear warheads yet remain vulnerable if they are concentrated in a few fixed and easily targeted locations.
Conversely, a smaller arsenal that is dispersed, mobile, and diversified across land, air, and sea platforms can provide a far more credible deterrent. This distinction explains the difference between capability and assured capability. Capability refers to the theoretical ability to retaliate, whereas assurance exists when an adversary is convinced that retaliatory forces will survive and will certainly be employed if attacked.
Pakistan’s nuclear posture has increasingly reflected this logic. The development of the Babur cruise missile in both land-attack and sea-launched variants, efforts to establish a sea-based deterrent through Agosta-class submarines and future submarine platforms, and the diversification of delivery systems all point towards reducing single-point vulnerabilities.
The underlying rationale is straightforward: if Pakistan’s retaliatory forces cannot be neutralised in a single strike, there is little incentive for an adversary to attempt one. This is fundamentally a strategy of defensive deterrence rather than escalation.
India has similarly sought to enhance the survivability of its nuclear forces. The induction of INS Arihant, continued development of K-series submarine-launched ballistic missiles, and deployment of long-range systems such as the Agni-V have significantly expanded India’s strategic reach beyond the immediate South Asian theatre.
Officially, these developments are framed within the doctrine of credible minimum deterrence. However, the steady expansion of delivery systems, operational redundancy, and strategic reach suggests a gradual evolution beyond the traditional interpretation of minimum deterrence.
This is where the principal danger emerges. As both states simultaneously pursue greater survivability without sustained dialogue on doctrine or strategic intent, measures designed to strengthen deterrence may instead fuel a competitive arms race. Actions viewed as defensive by one side are frequently interpreted as offensive modernisation by the other, resulting in increased weapons development, greater secrecy, and deeper mistrust.
Such dynamics heighten the risk of crisis instability, particularly when neither side clearly understands the other’s red lines or escalation thresholds. The Pulwama-Balakot crisis and repeated tensions over Kashmir illustrate how rapidly conventional confrontations can generate nuclear anxiety, even without any actual use of nuclear weapons.
Reducing these risks does not require either country to abandon efforts to strengthen survivability, as such measures are rational responses to genuine security concerns. Instead, both sides should reinforce existing confidence-building measures, including pre-notification of missile tests, stronger military hotlines, and greater use of Track-II or backchannel dialogue on nuclear doctrine.
Formal arms-control agreements may remain politically difficult, but limited communication on strategic intentions can reduce dangerous misunderstandings. Neither country needs to reveal sensitive operational details to signal strategic restraint.
Lasting stability in South Asia has never depended on numerical parity in nuclear arsenals. It has always rested on the confidence of both sides that a first strike cannot eliminate the other’s ability to retaliate. As Pakistan and India continue modernising their second-strike capabilities, regional stability will depend less on the number of nuclear weapons they possess and more on whether confidence, or mutual mistrust, shapes the future of their nuclear doctrines.
Muhammad Ibrahim Nadeem is a student of International Relations at the National Defence University, Islamabad, with research interests in geopolitics, strategic studies, and South Asian security. He writes on nuclear deterrence, regional stability, and foreign policy, aiming to make complex strategic issues accessible through evidence-based analysis.
