As the death toll rises, Indian police begin the interrogation of captured terrorists, and messages of sympathy, solidarity and support pour in from around the world, Indian suspicions are hardening that one country in particular bears a heavy responsibility for the atrocities that have shaken Bombay: Pakistan.

It is not simply the telephone intercepts, the seaborne trail leading back to Karachi and the capture of at least one Pakistani national; it is the timing, planning detail and coordination that strongly suggest the terrorist attack could not have been mounted without the acquiescence, if not the surreptitious assistance, of Pakistan. India yesterday warned Islamabad that it must dismantle the infrastructure supporting terrorism, and Manmohan Singh, the Prime Minister, spoke of a “cost” if it failed to do so. It is a warning that should be repeated, unambiguously and publicly if necessary, by Washington and its allies in the West. And it is one that has already forced Pakistan to take the unusual step of sending the head of its military intelligence agency, ISI, to India to help with the investigation.

ISI’s desperate aim will be to convince India that President Zardari’s Government is itself a victim of terrorism and had no hand in this atrocity. It will be hard to show, however, that militants linked to al-Qaeda have not been supported by elements within ISI itself, or that the Pakistani Government has cracked down on all extremist Islamist groups or curbed its long-standing reflex of using India as a diversionary threat when beleaguered by internal divisions.

A more fundamental question is whether al-Qaeda can be defeated. On one level, the answer is yes. The puritanical vision of a unified Islamic theocracy at permanent war with nonMuslims no longer appeals even to alienated young Muslims. Not only is its anachronistic conception of a new caliphate unfeasible; in Bradford as well as Baghdad, Muslims find the carnage orchestrated from caves on the Afghan border an insult to their faith. Al-Qaeda’s warped vision has been defeated where it had hoped to take root: in Iraq, where ordinary people have turned against jihadists from outside their borders, and in Saudi Arabia, where an extensive programme to reeducate and reintegrate young extremists has proved remarkably successful.

On another level, however, al-Qaeda has shown Protean resilience, not so much as an organisation but as a franchise. It has allied itself to local Islamist groups, leasing its name and methods, and lending a spurious ideology to nihilists and those seeking to exploit religion as a means to power. The al-Qaeda brand has now been adopted across the Maghreb, where Algerian and Moroccan Islamists seek to regroup after recent setbacks; in Somalia, where al-Qaeda can pose as the spearhead of resistance to the Ethiopians and to Western influence; and on the periphery of the Muslim world where insurgents in the Philippine jungles or in Indonesia are seeking the overthrow of established governments.

Here, the defeat of al-Qaeda will prove much harder. For the enemy is not only the West but all those corrupt and ineffective governments whose clumsy repression has recruited so many to the zealots’ cause. What al-Qaeda seeks to do is to stage operations of such spectacular cruelty that public anger turns on Muslim minorities or backs harsh new repressions that unify the fearful and deliver them to the militants.

The campaign waged by the West against al-Qaeda’s leaders must continue, including the missiles attacks on their hideouts. But just as the ideological defeat of al-Qaeda is possible only by liberal democracy, country by country, so India’s victory is achieved by forbearance and the maintenance of a secular, tolerant society.