IN what sense were the World Trade Centre bombers members of Islam? This question has been sidelined by many Western analysts impatient with the niceties of theology; but it may be the key to understanding the recent attacks, and assessing the long-term prospects for peace in the Muslim world.
Certainly, neither bin Laden nor his principal associate, Ayman al-Zawahiri, are graduates of Islamic universities or seminaries. And so their proclamations ignore 14 centuries of Muslim scholarship, and instead take the form of lists of anti-American grievances and of Koranic quotations referring to early Muslim wars against Arab idolators. These are followed by the conclusion that all Americans, civilian and military, are to be wiped off the face of the Earth.
All this amounts to an odd and extreme violation of the normal methods of Islamic scholarship. Had the authors of such fatwas followed the norms of their religion, they would have had to acknowledge that no school of traditional Islam allows the targeting of civilians. An insurrectionist who kills non-combatants is guilty of baghy, "armed transgression", a capital offence in Islamic law. A jihad can be proclaimed only by a properly constituted state; anything else is pure vigilantism.
Defining orthodoxy in the mainstream Sunni version of Islam is difficult because the tradition has an egalitarian streak which makes it reluctant to produce hierarchies. Theologians and muftis emerge through the careful approval of their teachers, not because a formal teaching licence has been given them by a church-like institution.
Despite this apparent informality, there is such a thing as normal Sunni Muslim doctrine. It has been expressed fairly consistently down the centuries as a belief system derived from the Muslim scriptures by generations of learned comment. Until a few decades ago, a Koranic commentary containing the author's personal views would have been dismissed as outrageous. In the 19th century, the Iranian reformer known as "the Bab" was declared to be outside the pale of Islam because he ignored the accumulated discussions of centuries, and wrote a Koranic commentary based on his own direct understanding of scripture.
The strangeness as well as the extremity of the New York attacks has been reflected in the strenuous denunciations we have heard from Muslim leaders around the world. For them, this has been a rare moment of unity. Mohammed Tantawi, rector of Cairo's Al-Azhar University, the highest institution of learning in the Sunni world, has bitterly condemned the outrages. In Shi'ite Iran, Ayatollah Kashani called the attacks "catastrophic", and demanded a global mobilisation against the culprits. The Organisation of the Islamic Conference, normally well known for its indecision, unanimously condemned "these savage and criminal acts".
Why should apparently devout Muslims have defied the unanimous verdict of Islamic law? The reasons - and the blame - are to be found on both sides of the divide which, according to bin Laden, utterly separates the West from Islam.
On the Western side, a reluctance to challenge the Israeli occupation of Muslim holy sites in Jerusalem has unquestionably contributed to the sidelining of mainstream Muslim voices in the Middle East. Those voices, speaking cautiously from ancient religious universities and venerable mosques, have been reluctant to exploit, rather than calm, the hatred of the masses for Israeli policy, and thus for the United States. This perceived failure to make a difference has allowed wilder, more intransigent voices to gain credibility in a way that would have been unimaginable before the capture of Arab Jerusalem in 1967.
It is unfair and simplistic, however, to claim that it is Western policy that lit the fuse for last month's events. Without a theological position justifying the rejection of the mainstream position, the frustration with orthodoxy would have led to a frustration with religion - and then to a search for secular responses.
That alternative theology does, however, exist. While Saudi Arabia itself has been consistent in its opposition to terrorism, it has also on occasion unwittingly nurtured revolutionary religious views. Before the explosion of oil wealth in the 1960s, its Wahhabi creed was largely unnoticed by the wider Islamic world. Those erudite Muslims who did know about Wahhabism typically dismissed it as simple-minded Bedouin puritanism with nothing to add to their central activity - exploring Muslim strategies of accommodation with the modern world.
When I myself studied theology at Al-Azhar, we were told that Wahhabism was heretical - not only because of issues such as its insistence that the Koranic talk of God's likeness to humanity was to be taken literally, but also because it implied a radical rejection of all Muslim scholarship. Grey-bearded sheikhs departed from their usual imperturbability to denounce the tragic consequences for Islam of the claim that every believer should interpret the scriptures according to his own lights.
This sort of radical move leads to liberal re-readings of the Koran, as in the case of the South African theologian Farid Esack, who has horrified traditionalists by advocating homosexual rights among Muslims. Much more commonly, however, it allows young men whose anger has been aroused by American policy in the Middle East to ignore the scholarly consensus about the meaning of the Koran, and read their own frustrations into the text.
Another result of this rejection of traditional Islam has been the notion that political power should be in the hands of men of religion. When he came to power in 1979, Ayatollah Khomeini remarked that he had achieved something utterly without precedent in Islamic history. The Taliban, by ruling directly rather than advising hereditary rulers, have similarly combined the "sword" and the "pen". Far from being a traditionalist move, this is a new departure for Islam, and mainstream scholarship regards it with deep suspicion.
Islamic civilisation has in the past proved capable of, for the times, extraordinary feats of toleration. Under the Muslims, medieval Spain became a haven for diverse religions and sects. Following the Christian reconquest, the Inquisition eliminated all dissent. The notion that Islamic civilisation is inherently less capable of tolerance and compassion than any other is hard to square with the facts.
Muslims none the less have to face the challenge posed by the new heresies. The Muslim world can ill afford to lapse into bigotry at a point in history when dialogue and conviviality have never been more important.
It is a relief that the mainstream theologians have come out so unanimously against the terrorists. What we must now ask them is to campaign more strongly against the aberrant doctrines that underpin them.
Both "sides", therefore, have a responsibility to act. The West must drain the swamp of rage by securing a fair resolution of the Palestinian tragedy. But it is the responsibility of the Islamic world to de- feat the terrorist aberration theologically.
Tim Winter [Abdul Hakim Murad], a Muslim, is lecturer in Islamic Studies at the University of Cambridge.