The death toll from last week's staggeringly brutal attacks by suicide bombers on two small-town communities in northern Iraq has crept up above 500, making it by far the worst atrocity since the 2003 invasion. No other mass killing has come within even half that total.Why did four truck bombers make these people their target? The mind struggles for an answer. The Yezidis are one of Iraq's smallest religious minorities, who follow an ancient cult unique to themselves. They wield no political or economic power. They live in an area that is remote from the key cities at the eye of Iraq's recurring hurricanes.
Yet there is a potential explanation for their killing, if such things can ever be explained. It carries a lesson for Iraq's future that goes much further than the tragedy of two marginal communities, and by coincidence has echoes in other events that occurred last week - the ceremonies marking 60 years since India's independence. The key word is partition, and the lesson is "Beware partition".
Most media coverage of the Yezidi massacre has concentrated on its religious dimension. Reporters pointed to the recent "honour killing" by a stone-throwing Yezidi mob of a young Yezidi girl who married a Muslim and apparently then converted to Islam. The killing was filmed and put on the internet. Sunni Arab extremists linked to al-Qaida then took their anger out, it seems, against the whole Yezidi community.
But, as the Guardian's Michael Howard pointed out, the ethnic dimension may be more important. Yezidis are Kurds and they live in areas that are being increasingly contested. According to Iraq's constitution, a referendum is supposed to be held there by the end of this year on whether to join the autonomous region of Kurdistan. Eliminating the Yezidis reduces the chances of the referendum going in favour of the Kurds.
Long before last week's atrocity, ethnic cleansing was under way elsewhere in Nineveh province and its capital city, Mosul. Like the British in Basra who have given up trying to stop intra-Shia strife, the Americans in Mosul have proved powerless to prevent that city's battle between Arabs and Kurds. The eastern half of the city and the adjacent Nineveh plains are Kurdish. The west is largely Arab, now the Yezidi are being intimidated to leave. Christian and Turcoman communities in the region look on anxiously, or flee. In Kirkuk, a contested city in one of Iraq's best oil regions, ethnic cleansing is also going on, albeit on a less dramatic scale.
It is a fair bet that if these various regions - which the Kurds claim as ancestral lands - were not threatened with frontier changes much of this violence would be reduced.
To the bureaucratic eye, partition seems a neat solution. But it often creates more problems than it solves. Where does the new border line run, and who will be in charge of drawing it? In India Cyril Radcliffe, a British lawyer with no experience of the area, working largely with maps and consulting none of the affected people, carved up the subcontinent in less than five weeks. As he worked, ethnic cleansing and killing accelerated as Hindus, Sikhs and Muslims tried to show they were the majority in every multicultural district.
What happens to minorities who are "left behind" and find themselves outside the new entity where their group forms a majority? They are often "transferred" against their will, or forced to flee like the Hindus of Lahore. Some argue that without partition the killing in India would have been worse, and that the atrocities of 1947 and 1948 affected only a small percentage of the region's population. Independent India had then, and still has, more Muslim citizens than Pakistan - eloquent proof that they live normally in a state that prides itself on its multi-ethnic, multireligious identity.
Today's Iraq is very far from that. But this does not mean that it cannot one day revert to the multicultural tolerance it enjoyed in the pre-Saddam era. Sectarianism was deliberately cultivated by him on a "divide and repress" basis. The occupation forces then made the mistake of using sectarian and ethnic criteria for selecting the Iraqis they wanted as their postwar allies. Finally, attracted into Iraq by the chance to humiliate Americans as they were to Afghanistan against the Russians two decades earlier, al-Qaida joined the mix by infiltrating Iraq and deliberately provoking sectarian violence through targeting Shia civilians with suicide bombs.
Grim though the result is, today's heightened ethnic and sectarian consciousness in Iraq's towns and cities is not a result of ancient hatreds. It is too early to abandon hope that it can be reversed, or that Iraq can one day be liberated from the interference of foreigners, whether they are western troops or Islamic jihadis.
Those who argue for partition only exacerbate tensions. Many Kurds want it, but it is not the dominant Shia or Sunni view. Surveys of attitudes in Iraq still show more Arabs define themselves as Iraqis than as Sunnis or Shias. To his credit, George Bush has not advocated partition, nor does it seem to be part of his hidden agenda. His remarks this week about Vietnam and what followed in Indochina after the US left, as well as his refusal to contemplate any withdrawal from Iraq while he remains president, were misguided and dangerous. At least he has not come out for splitting the country.
It is the Democrats who seem more tempted by it. Hillary Clinton has suggested keeping a substantial US force in Kurdistan if troops pull out of Baghdad and the south. So have Senator Joe Biden, another presidential candidate, and Richard Holbrooke, the former ambassador to the UN. They may be arguing this as a way of minimising the image of humiliation and retreat when the US eventually has to give up its foolish Iraqi venture. But it is wrong.
Meanwhile the deadline for the referendum on Kirkuk and the other contested regions in the north approaches. The priority must be to put it off until Iraq reaches some form of stability. It will be a bitter blow to the Kurdish political parties who have staked so much on it, but they will not risk violence in opposing a postponement. They have thrived in showing the world they can run their own region responsibly. Let them be satisfied with what they have, and not insist on having more just now.
Jonathan Steele