India was in big trouble before these terrorist attacks, despite its recent dazzling success. They may have a serious effect on its stability, which is not as solid as its image suggests.

For a start, they are a threat to the Government of Manmohan Singh and the Congress Party, which already looked vulnerable in six imminent state elections, and the general election due by May. The Prime Minister, on whom huge hopes once rested, has faced horrible obstacles. But he is still open to charges of having wasted India’s best chance of deep reform in years by his timidity and failure to control his Cabinet or corruption.

The immediate risk is that the attacks provoke a Hindu backlash, strengthening hardliners within the resurgent BJP Hindu nationalist party. The party is increasingly inspired by an ideology that challenges the entire basis of India as a secular democracy, offering equal rights to Muslims and others.

Singh, an immensely likeable public figure, gave a good short speech yesterday, understated but direct in conveying the gravity and shock of the assault. His remark that the terrorists seemed to have “external links” is the kind of phrase often used by Indian politicians to imply Pakistani responsibility, but Singh carefully did not say that. It helped that Shah Mehmood Quereshi, Pakistan’s Foreign Minister, in Delhi for the stuttering talks on Kashmir, condemned the attacks and called for joint efforts to defeat terrorism.

Nor does a direct Pakistani link seem likely, although some Indian channels speculated that the attacks might be the work of Lashkar e-Taiba, the most organised of the Pakistani militant groups. But a direct role by LET, even in sending militants over the border, seems unlikely. True, LET (which renamed itself Jammat al-Dawaat in 2002 to sidestep a government ban) remains large and coherent, but its obsession is Kashmir. The group claiming responsibility for these attacks made no mention of this old cause.

Nor is Jaish e-Mohammed, the other bulwark of Pakistan-based terrorism, a likely perpetrator. It carried out the December 2001 attack on the Indian Parliament, but since the ban on its activities that followed, it fragmented. Its cells are said to be close to al-Qaeda elements in the tribal areas, but it is still hard to think it has the scale for these attacks.

At this point, then, those responsible seem most likely to lie within al-Qaeda, or to have come from new radical Islamic groups within India. That is the great worry for India. The threat of Hindu-Muslim conflict has been growing, in parallel with economic glory. Singh, as Finance Minister, was the architect of reforms that unlocked that growth. But in his four years as Prime Minister he has failed to take the project on, fuelling the resentment of groups aggrieved for different reasons.

It is true that Singh was blocked by problems not of his making. Communists in his coalition hated his market reforms; he got up courage to ditch them only this year. Nor has he been helped by Sonia Gandhi, who as head of the party, dodged tough reforms, favouring social welfare to shore up support in rural areas. But these were expensive, and funds have vanished in corruption. Singh can be blamed most for failing to impose order on his Cabinet. Personally honest, he did too little to answer allegations of corruption or just indolence about the team.

Rising anger has allowed the BJP to regain its old strength. Under Atal Behari Vajpayee, Prime Minister from 1998 to 2004, it proved moderate (notably in Kashmir talks with Pakistan), but now it is led by the harder-edged Lal Krishna Advani, 81. His speeches helped to stir up the Hindu mobs that destroyed a mosque in 1992, leading to the deaths of 2,000, although he was cleared of incitement. His most likely successor is Narendra Modi, who as chief minister has turned Gujarat into an economic powerhouse, but was denied entry to the US in 2005 for his alleged part in the 2002 Gujarat riots.

The BJP does not pose a threat to India’s future because its economic policies are so different from those of Congress. But it is influenced by an ideology which argues that India should be an all-Hindu state. India’s secular democracy, its proudest boast, is an obvious target for religious militants. Their aim, surely, is national Hindu-Muslim conflict, and it is not impossible to imagine. That would be a disaster in a country whose outstanding achievements have still left it vulnerable to dangerous divisions.

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