India and Pakistan can be compared with a pair of twin disgruntled siblings, perennially in a state of squabbling. Both were born as independent countries in August 1947, when the British beat a hasty retreat, unable or unwilling to confront the burgeoning animosity between British India's two most prominent communities, Hindus and Muslims. Thereafter, each had its own sovereign Dominion within the British Commonwealth, later transforming into Republics. As quick departures often entail, the British left back a bunch of unfinished business. One of them was in regard to territorial borders which remained undemarcated . British India was dotted with Princely States which were given an option to join either India or Pakistan. Circumstances rendered the State of Jammu and Kashmir an apple of discord into which both began to nibble and bite. An intractable dispute followed. Wars resulted, and while both claimed the entire territory, India secured a significant portion and Pakistan a smaller segment. There have been periods of calm in their relationship, but these have been few and far between. Today both India and Pakistan are nuclear-armed States, deterring each other at the highest level of conflict. At this time their relations seem to have reached a low nadir. The world which had learnt to live with the India-Pakistan rivalry is now deeply concerned that the situation may become destabilizing enough to upset this fragile equilibrium.

Three factors have exacerbated the situation. One is the recent decision of the nationalist Bharatiya Janata Party (BJP) government of Indian Prime Minister Narendra Modi which, carrying out an electoral pledge has decided to revoke Article 370 of the Indian Constitution which had given the troubled State of Jammu and Kashmir, creating instead two Union territories of Kashmir and also Ladakh , for which incidentally China is also a claimant. Immediately unrest swept that region and India brought to bear on it a fierce security clampdown. A second factor was the commitment of the BJP to Hindutva, the Hindu way of life in what was otherwise seen as a secular Union Republic. Also, several legislations concerning 'nationality issues' were adopted which are largely being interpreted by Indian Muslims as discriminatory. It is threatening to deepen the Hindu-Muslim divide in the country, with dangers of it spilling into the rest of the subcontinent. For historical reasons, Pakistanis feel a sense of empathy with co-religionists in India, and the consequence is a worsening State to state relations. A third is that the decision with regard to Ladakh, have given China umbrage. Beijing is now keen to revive the dispute in the United Nations, and work with its ally Pakistan to that end, bringing the two together, potentially even militarily in the current confrontation with India, thus encouraging and enhancing the prospects of a conflict.

How do India and Pakistan see their nuclear weapons in this conflictual equation between their two countries? India, of course, has also China to worry about. At present India is said to possess 130 to 140 nuclear warheads, while plutonium production facilities are preparing to produce more for missiles now under development. New plans include the production of Nirbhoy, a ground based cruise missile similar to America's Tomahawk, and Dhanush a shorter-range sea-based missile. There is a heavy reliance on bombers for long range delivery, and this is evident in the plans to purchase 36 French Rafale fighters, also equipped to carry bombs. There are land-based missiles, such as Agni and Prithvi, mainly with Pakistan in view.

Concerns were aggravated both regionally and globally when India's strict 'no first use' doctrine was called into question last August by a person no other than India's Defence Minister, Rajnath Singh. Singh recently said that while 'No first use' was the earlier nuclear policy, 'what happens in the future depends on circumstances.' While in rhetorical terms this may appear to be a shift, in practical calculations stated doctrinal positions on the use of nuclear weapons are unlikely to be taken seriously by adversaries. Their logical extrapolation would be that the possession of (nuclear-weapon) capability at all times implies the possibility, even probability of use, as determined by strategic factors, irrespective of earlier political pronouncements.

Pakistan, who has a single adversary, India, reportedly has 150 to 160 warheads. It is the weaker of the two parties. Unsurprisingly, therefore, Pakistan had always eschewed the 'no first use' doctrine. As was the case with NATO troops in Europe pitted against the conventionally superior Warsaw Pact armies during the cold car, where the rolling of Soviet tanks into Germany was deemed to have an automatic 'tripwire' effect unleashing allied nuclear retaliation, Pakistan had always claimed to keep the nuclear option alive. It was to be activated if conventionally overwhelmed by the enemy. True, in the past Pakistan's stated preferred choice was 'minimum credible deterrence' that would involve the use of nuclear weapons as a last resort. But then, reacting to such Indian plans as 'Cold Start', which implied occupation of Pakistani territory at early stages of warfare and conducting strikes therefrom, Pakistan began to build low-yield, tactical and theatre warheads as an early potential response to aggression. From 'minimum credible deterrence' the doctrine morphed into 'full spectrum deterrence', with the deployment of tactical weapons. The tactical capability is largely reliant on a solid-fuelled ballistic missile capable of mounting a sub-kiloton missile, rather dauntingly named Hatf, which means 'vengeance'. Indians and Pakistanis have a penchant for giving their weapon-systems fearsome names, perhaps to add to the perceptions of their lethality. For instance, the name of Arihant for the Indian nuclear submarine, which means 'killer of enemies'.

For the traditional nuclear States deterrence was buttressed by the fear of 'mutually assured destruction', labelled MAD by strategists. But that was predicated on cold and rational mathematical calculations of consequences. Passions in south Asia run high, and when religious beliefs factor into decision-making, rationality can become clouded. This is an additional danger in the Indo-Pakistani balance. The equilibrium can also be upset by what has been called the 'Thucydides syndrome'. That Greek historian had famously observed in classical times that 'when Athens grew strong, there was great fear in Sparta and war was inevitable'. There is the danger that one side may reason that there was an optical moment to strike or the other would grow too strong to tackle later.

Shorter-range missiles and low-yield nuclear weapons increase the propensity for use. It may give an impression of lower fatalities, thus encouraging 'nuclear-warfighting'. But once such fighting begins, escalation of a 'limited nuclear war' into an all-out conflict will be inevitable, and immediate. In this vastly populous and compact region a nuclear war will surely be an Armageddon in which destruction will engulf all. There would be no winners, only losers. The understanding of this simple but incontrovertible logic cannot possibly escape the concerned leaderships.

Dr Iftekhar Ahmed Chowdhury is Principal Research Fellow at ISAS, National University of Singapore, former Foreign Advisor and President of Cosmos Foundation Bangladesh