Those who worry about the effectiveness of our deterrent should concentrate on ensuring the survivability of the fission weapons in the event of a first strike rather than on building an unnecessary arsenal of H bombs.

Some time ago, the former defence scientist, K. Santhanam, came out with the comment that the actual yield of the thermonuclear device (H-bomb) tested in 1998 was significantly lower than what it was designed to do and what, for that matter, was claimed by the Department of Atomic Energy (DAE) after the explosion. This is a not a new controversy. Soon after the tests, the official claims of yield were contested by independent analysts both in India and abroad, followed by detailed rebuttals by DAE officials. The dispute was never really resolved, with the officials on one side and the critics of the tests on the other maintaining their stands. But, given that Dr. Santhanam was one of the key scientists overseeing those tests, his recent comments created quite a furore in the media and in political circles.

But within a few days the controversy over the thermonuclear “fizzle” has already died down, even though the substantive differences on the success of the 1998 test continue to remain. The media, as they are wont to do, have moved on to other topical matters. And, as we will argue below, that is just as well. The failure of that thermonuclear device, even if true, is not as serious a matter for our national security as has been made out to be by some commentators.

Our nuclear policy

People getting agitated over the alleged failure of the thermonuclear test should remind themselves of what our stated policy on nuclear weapons is. In a remarkable act of transparency in what is generally viewed as an area of extreme secrecy, our nuclear policy was spelt out in the draft Indian Nuclear Doctrine of 1999, subsequently formalised with some modifications in 2003. As made explicit in that document, India, unlike the cold warriors of the ‘fifties, embarked on making nuclear weapons not as a war fighting arsenal or for use in a massive first strike, but only as an instrument of minimal nuclear deterrence. This deterrence was to be achieved with “…..sufficient nuclear weapons to inflict destruction and punishment that the aggressor will find unacceptable…”

This policy has been repeatedly underlined and reiterated several times by the government of the day, despite efforts by hawks bent on adopting a more aggressive nuclear posture. It remains our national policy till today. Therefore the sufficiency or otherwise of our nuclear arsenal should be measured against the standard of what minimal deterrence really requires.

Imprecise concept

The concept of minimal deterrence is admittedly imprecise in quantitative terms. Its foundations are as much psychological as logical since it hinges on how much damage would be “unacceptable” to your adversary. Nevertheless, certain basic aspects of minimal deterrence are clear. Firstly, it does not call for a boundless open-ended arsenal. It does not even require that your offensive weapons match in number or strength those of your adversaries. It only demands that you have enough capability, in a second strike, to inflict “unacceptable damage” to the other side, should they be so foolish as to initiate a nuclear attack on us.

How much capability does one need for the purpose? Well, the holocaust of Hiroshima and Nagasaki has explicitly demonstrated the damage that the simplest fission weapons can do. Hiroshima was bombed with a uranium-based weapon of about 15 kT (kilotons) and well over a lakh of people were killed. Nagasaki was hit by a plutonium based weapon of about 20 kT which killed over 80,000 people — a somewhat smaller number than in the case of Hiroshima because of its hilly terrain. Some estimates place the fatality counts in both these towns even higher.

Today’s major cities of China and Pakistan have a much higher population density than did Hiroshima and Nagasaki in the ‘forties. There is little doubt that a single 15-20 kT fission weapon dropped on, say, Karachi or Shanghai will kill over a 150,000 people. Thus two bombs dropped on separate localities in Karachi and two over Lahore, (or similarly over Beijing and Shanghai) will conservatively cause half a million fatalities.

Surely, that should be “unacceptable damage” to even a remotely responsible leadership in any modern country. Do proponents of bigger thermonuclear weapons really believe that any foreseeable leadership in China would take the risk of initiating a nuclear first strike at the cost of a guaranteed response that can kill a half a million of its own people and render two major cities unlivable? I don’t believe the Chinese would ever take such a risk. The same applies to Pakistan, whose present and past governments, whatever be their other deficiencies, would consider an unprovoked nuclear first strike if the cost is to be the lives of half a million citizens of Karachi and Lahore.

The spectre of jihadi militants taking over Pakistan is often raised as an argument against this logic. It may be argued that such a fanatical leadership may be willing to accept even half a million fatalities as a price for its jihad. Such a possibility cannot be ruled out. But any leadership that finds half a million civilian fatalities “acceptable” is in any case beyond the pale of rationality. It cannot be relied upon to feel deterred by the prospect of even a much larger attack.

Irrational adversary

True, a 200 kT H-bomb will inflict damage over four to five times as large an area as a 20 kT fission bomb will. So, it may end up killing a few lakhs of people instead of one lakh. But if a fanatical “leadership” on the other side is bent on a suicidal adventure and willing to sacrifice a lakh of its civilians, will it be deterred just by increasing the casualties a few fold? Deterrence has no meaning in that situation and building a larger, thermonuclear weapon is not the answer to such an irrational suicidal adversary.

In short, a thermonuclear hydrogen bomb is not crucial for minimal deterrence. Standard 20 kT fission weapons will more than suffice. Pokhran I and II have exploded those successfully. The recent controversy does not cast doubt on that. While the international community of nuclear experts may differ on whether India has 40 or 100 fission bombs in its arsenal no one, as far as I know, questions India’s ability to produce fission weapons.

As a corollary, whether the H-bomb test fizzled or not is not something that vitally affects national security or compromises our minimal deterrence capabilities. Those who worry about the effectiveness of our deterrent should concentrate on ensuring the survivability of the fission weapons in the event of a first strike rather than on building an unnecessary arsenal of H bombs.

There is a small segment of our strategic community which keeps pushing for a more aggressive nuclear posture. They surfaced again during the recent fizzle controversy. No doubt they sincerely believe that their strategy is good for the country. But they don’t come out and openly say that what they suggest goes beyond the declared national policy of minimal deterrence.

It is not easy to resist such hawkish demands since it also has the support, whether willingly sought or not, of chest thumping chauvinists. Nevertheless, sober national security policy makers should ensure that they don’t succumb to the pressure to up the nuclear ante. They should remain firm with the existing policy that the aim of our nuclear arsenal is only to deter others from attacking us and not to wage nuclear wars or to maximise casualties on the other side as an end in itself.

(R. Rajaraman is Emeritus Professor of Physics, Jawaharlal Nehru University, New Delhi, and Co-Chair, International Panel on Fissile Materials.)

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