For almost a year the Bush Administration in Washington and the Karzai Government in Kabul have been putting out feelers to India to give its aid to Afghanistan a military dimension. There are signs that elements within the coalition of Manmohan Singh, the Indian Prime Minister, may be interested.

So, was Monday's bombing of the Indian Embassy in Kabul a warning to Delhi not to deepen its involvement in Afghanistan? The attack that claimed 41 lives, including the military attaché, and injured 141 was the biggest in Kabul since the fall of the Taleban in 2002.

India is involved in training Afghan military personnel. It has “exchange of intelligence” accords that have enabled Kabul to track down groups linked to the Taleban. India is the second-largest aid donor to Afghanistan, behind the US and ahead of Iran. It has allocated about $750 million to rebuild the war-shattered infrastructure. This includes strategic roads that have helped the Afghan Army and Nato allies to pursue Taleban fighters in previously inaccessible areas.

Of the regional powers, only India has offered full support to post-Taleban Afghanistan. China regards the regime of Hamid Karzai as too beholden to the US and too hostile to Pakistan, its traditional ally in South Asia, while Russia cannot come back because of memories of the Soviet invasion in the 1980s.

Most Afghans, who are Sunni Muslims and fear that Khomeinist mullahs might want to impose Shia Islam, regard Iran with suspicion. Pakistan is perceived as hostile because it created the Taleban and supported it for years. Afghan nationalists also lay claim to Pakistan's Northwest Frontier Province (NWFP) where fellow Pashtuns, the largest ethnic group in Afghanistan, are a majority.

That leaves India as the only regional power committed to a new democratic Afghanistan. It was no accident that India shouldered part of the cost of the parliamentary and presidential elections. Nor should one ignore the symbolic value of the fact that India is building the new Palace of Democracy to house the Afghan parliament.

Enemies of the new Afghanistan believe that the US cannot sustain long-term commitment to the regime. Americans are tired of distant wars and find it increasingly hard to fight in a tough land with no oil and plenty of opium poppies. Once the US leaves, other Nato powers would head for the door.

The only power likely to offer Afghanistan long-term support is India. Helping Afghanistan would weaken radical Islamism and prevent Pakistan acquiring a hinterland through Afghanistan in Muslim Central Asia. At some point, Delhi might consider military commitment, an idea that is surprisingly popular in India but regarded with horror in Pakistan.

Thus, plenty of people have an interest in scaring the Indians out of Afghanistan. The Taleban see India as the only regional enemy capable of resisting them. Pakistan knows that an Afghan-Indian alliance would leave it isolated, especially when Iran is making mischief by financing a rebellion in Pakistani Baluchistan.

The Afghan authorities all but pointed the finger at Pakistan's military intelligence, the ISI, a theory that cannot be dismissed out of hand. Somewhat weakened in the past four years, the ISI may be trying to make a comeback while the ruling elite in Islamabad is engaged in internecine feuds. Some in the Pakistani military, including the generals Aslam Beg and Hamid Gul, resent “democracy imposed by the US” and claim that only the Army and ISI can protect independence.

They may think that the weakness of the coalition Government offers a chance to regain lost influence. They may also want further to humiliate President Pervez Musharraf, now isolated and unable to pursue his policy of purging the ISI. His foes may also want to break the fragile truce with India that is his most important legacy.

Hatred of India and hope of capturing what is left of Kashmir in Indian hands have always formed part of the glue that holds Pakistan together. Monday's attack in Kabul puts India and Kashmir back at the centre of the Jihadist agenda. It may also persuade the terrorists to tone down attacks in Pakistan in the hope of securing revived ISI support for attacks in Afghanistan and India.

The US could still use its influence in Islamabad to persuade the new Government to maintain Mr Musharraf's policy of restructuring the ISI and co-operating with Afghanistan in the War against Terror. Blaming the ISI, however, does not absolve the Karzai regime of its responsibility. Mired in corruption and often paralysed by the incompetence of its officials, it has lost much of its popular base.

For the first time since 2002, the Taleban controls almost half of Wardak, the province that starts on the edge of Kabul, far beyond their traditional strongholds in Helmand and Arzangan. Elsewhere, former warlords are returning to fill the “authority gap” left by Mr Karzai's dithering rule. The US could force Mr Karzai to stop blocking reform and dismiss corrupt cronies.

Monday's attack was aimed against both India and Afghanistan. The response must come in the form of greater determination to resist terrorism but an even greater readiness to regain the confidence of the Afghan people - without which no amount of foreign military commitment, including India's, could ensure victory.

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