Nuclear bombs back on world agenda

THE announcement yesterday by India's Prime Minister, Atal Behari Vajpayee, that it conducted three nuclear tests is an abrupt and brutal reminder that, despite the end of the Cold War and the approval two years ago of the Comprehensive Test Ban Treaty, nuclear weapons are very much alive, coveted and dangerous. The immediate probable consequence of the decision will be to catapult the nuclear-testing issue right to the top of the agenda for this weekend's G8 summit in Birmingham.

Almost certainly too, it pushes back the day when the CTBT, endorsed by the United Nations General Assembly in September 1996, becomes fully operational. In the longer term, however, it could put pressure on the five acknowledged nuclear powers of Britain, France, Russia, the US and China, to rid themselves of the weapons entirely.

Although it has been signed by 149 countries, and ratified by 13 including Britain and France last month, the treaty will not "enter into force" - to use the official jargon - until it has been ratified by all 44 countries which possess nuclear weapons or nuclear reactors which could be used to build such weapons.

But North Korea, Pakistan and India - which has described the CTBT as "a charade" because the five acknowledged powers were not giving up their weapons - have refused to sign it. Thus two of the three "threshold nuclear" powers, assumed to have nuclear weapons or be capable of assembling one at short notice, have refused to sign, while the third, Israel, (which has signed) is believed to possess between 100 and 200 warheads.

As for North Korea's programme, its stage of development is unclear, but urgent US-led efforts are under way to contain it, bargaining economic aid for public scrutiny of North Korean installations.

No such leverage is available with India, whose ruling BJP Hindu nationalist party fought the March election on a specific platform of keeping the nuclear option open.

Reactions by prominent Indians yesterday only underlined how the tests had reinforced a sense of national pride and achievement:

"It's wonderful ... I'm speechless," said the former defence minister Raja Ramanna, while an ex-ambassador to Pakistan, Jyotindra Nath Dixit, hailed them as "a decisive test to ensure strategic security."

Neither remark suggests that India will meekly follow the example of France, which signed the CTBT after President Jacques Chirac in 1995 and 1996 carried out a bitterly contested but "final" series of tests at Mururoa atoll in the South Pacific. Nor does India's long- standing vow not to commit itself to ending nuclear tests while Pakistan retains the technology to build a nuclear weapon leave much room for manoeuvre.

Above all though, the timing of the announcement underlines the assertiveness of the nationalist-led government. It has acted in the full awareness that the tests will undermine the campaign of the world's second most populous country for a permanent seat on the UN Security Council.

It has chosen a moment just a few months ahead of an important visit to Delhi by President Bill Clinton, designed to inject warmth into long cool relations between Washington and the regional superpower of South Asia.

Given the current US pre-occupation with nuclear proliferation, the White House reaction of "deep disappointment" was utterly predictable.

Indeed, Mr Clinton may now prefer to put the trip off entirely.

Delhi's intransigence leaves the international community with few options. Economic sanctions are one possibility, and theoretically could be triggered by recent congressional legislation, which gives Mr Clinton 30 days to impose them against a country which conducts a nuclear test. The White House last night was not tipping its hand, but sanctions in any case could be imposed at a CTBT review conference in 1999. Experts doubt they would have much effect.

The real worry is that Pakistan might retaliate by carrying out a test of its own - or, worst of all, that China, which has signed up, would resume testing. Such a step would probably wreck the treaty, and turn the much-feared nuclear escalation in Asia into fact.

India's move is a direct response to Pakistan's recent testing of a surface- to-surface missile able to carry a nuclear warhead and hit targets 1,000 miles away.

Not that the CTBT is entirely toothless. Whatever happens, it will establish a world- wide system of monitoring stations employing hydro-acoustic, seismological and radiation-sensing equipment able to pick up a nuclear explosion of one kiloton or more anywhere in the world.

But India's provocative timing may have been quite deliberate. Its main motive for retaining the nuclear option is the belief it will ensure security against two traditionally hostile neighbours to the north-west and north- east.

But, as Dan Plesch of the disarmament group Basic contends, "the condemnation of the established nuclear powers only exposes the basic hypocrisy of the Big Five - of us saying to other countries `Do as we say, not as we do'."

Five weeks ago Robin Cook, the Foreign Secretary, hailed Britain's ratification of CTBT as proof of its "commitment to the goal of a nuclear-weapon free world."

In reality, however, Britain's nuclear deterrent was excluded from consideration at last year's strategic defence review initiated by the incoming Labour government. Hence India's argument that until existing nuclear weapons powers renounce them, they have no moral right to insist other countries do not seek to acquire them.

India LEAVES ITS signature

How do we know it was a test?

The "signature" detected by seismometers around the world can pinpoint an event, and indicates whether it was sudden (as with a bomb), or has the long-lasting resonance of a tectonic event (as in an earthquake). However, it's a difficult process.

What does a test indicate?

Most importantly that the country is capable of building a nuclear weapon. Nuclear tests transform a country's standing in the international arena.

What tests did India carry out?

Three, apparently simultaneously: a fission device, a low-yield device and a thermonuclear device.

What are these different tests?

A fission bomb uses enriched uranium (at least 15 kilograms of 90 per cent U-235), arranged as an empty sphere surrounded by high explosives. Those explode, imploding the uranium, which reaches a supercritical mass. Even then more neutrons are needed from metals such as beryllium and polonium to initiate a chain reaction.

The low-yield device was probably not nuclear at all: these tests are intended to simulate the effects of a nuclear explosion using non-nuclear or nuclear reactor sources. Basically, it's a way of developing warheads.

A thermonuclear device requires plutonium and produces an explosion so intense that fusion occurs. If India has achieved this, it has taken a huge nuclear step.

How big was the explosion?

According to US and Swiss experts, the incident was equivalent to an explosion of 10 kilotons of TNT. The Hiroshima bomb of 1945 was a 15-kiloton bomb.