On the afternoon of May 11th, India's prime minister, Atal Bihari Vajpayee, a man widely viewed as far too congenial for the hardline Hindu nationalists of his Bharatiya Janata Party, called a press conference and told the stunned journalists that New Delhi had blown up three nuclear devices in the western deserts of Rajasthan.
Mr Vajpayee spent the next few days being showered with rose petals, and beaming upon the crowds of middle-class, middle-aged men who danced in the street and screamed that India was at last a global player, and that the West would be obliged to give it respect.
Hindu nationalist groups vowed to collect the dust from the test site, at the medieval fortress town of Pokharan, and to distribute it to various shrines in the country. For the first time it began to look as if the aged and enfeebled prime minister liked his job, and the local press cracked jokes about Vajpayee's Viagra. "India is now a nuclear weapons state," the prime minister said.
And by May 29th, so was India's estranged twin. Pakistan tested its devices in the Chagai hills of Baluchistan, becoming the world's first Muslim state to go nuclear. The explosions, conducted in a chamber burrowed deep within the rock, were so forceful that the hills turned chalk white; the dust of ages had been shaken off.
Six months on, the sense of occasion that surrounded those twin detonations has vanished. In India and Pakistan, the nuclear tests have been eclipsed by political instability and economic debacle, damping down the bravado that erupted immediately following the detonations.
India's BJP, which had hoped to bind together a fractious ruling coalition in one great swell of national nuclear pride, is as beleaguered as before. Both countries have suffered from economic sanctions, although the US soon softened its regime to save Pakistan from outright collapse.
Already in arrears in repayments to international creditors, Pakistan may be unable to meet its next instalment of $300 million on a $32 billion foreign debt due early in 1999. In a desperate attempt to cut spending, Mr Sharif put entire ministerial buildings up for sale, and ordered his aides to drink green tea instead of black so as to save on milk.
Meanwhile, the armies of both countries are dug in along the old ceasefire line through the disputed territory of Kashmir. With a ready-made point of conflagration, a nuclear South Asia is a much more dangerous place. That has been a prime concern of US negotiators who have been trying to use the sanctions to leverage both India and Pakistan into entering peace negotiations on Kashmir, and into signing the Comprehensive Test Ban Treaty.
However, in early December India's defence minister George Fernandes announced that the secret talks with US negotiators had yielded nothing - a statement unlikely to end the chill between New Delhi and Washington. China too has felt the distance with India, especially as Mr Fernandes repeatedly had cited Delhi's perception of an increased threat from Beijing as a reason for the nuclear tests.
Under US prodding, Indian and Pakistani bureaucrats held two sets of talks in October and November both heralded by heavy exchanges of gunfire along the border. After the most recent session in New Delhi, diplomats admitted the two sides agreed in only one respect: that on all areas of discussion, they held positions that were unalterably opposed.
Until late November, Mr Vajpayee's BJP could be forgiven for believing that Indian pride outweighed strategic, diplomatic and economic reservations about the nuclear tests. In the media, the nuclear hawks were louder and more numerous than the nuclear doves - all two of them. The father of the bomb, APJ Abdul Kalam, was feted on television chat shows, and in the autumn had his newly-published memoirs serialised in the papers.
And so in the elections for legislative assemblies in four states on November 25th, the party manifesto said: "Our government chose to place India's security concerns above all other considerations, thus giving the much-needed boost to the morale of our jawans (soldiers) and our people, unleashing an unprecedented outpouring of national pride among Indians, both at home and abroad."
But voters were more concerned about food prices than pride - especially onions and potatoes whose prices shot up eight-fold. On average, prices of food staples went up some 20 per cent in the six months after the nuclear tests. The price rises arrived on the back of a recession - a product of a general reluctance among potential foreign investors to commit to a country viewed as unstable.
In the desert of western Rajasthan, villagers blamed the onion shortage on the tests directly - claiming that soldiers had filled the underground test pit with potatoes. The charges were unproven. But the party was unceremoniously thrown from office in Delhi and Rajasthan - coming fourth in areas where the nuclear devices were tested.
As Mr Vajpayee floundered, his Pakistani counterpart, Nawaz Sharif, tried to draw attention away from the economic disaster precipitated by the nuclear sanctions by adding to his personal power. On October 7th, he forced his army chief - who had complained about Mr Sharif's economic management - into premature retirement. Two days later, he introduced Islamic law, or Sharia, publicly expressing his admiration for the puritanical brand of Islam practised by the Taliban milita in neighbouring Afghanistan.
In December, Mr Sharif returned from a meeting with President Clinton in Washington with a promise of a $5.5 billion bailout from the IMF.
Government officials were coy about the conditions of the IMF largesse - and Mr Sharif's agreement to sign the CTBT. However, further economic hardship - including an end to subsidised power rates - appear inescapable.
So does further instability, for India as well as Pakistan.