After reconnecting, in January 2003, Garang and Darfur's guerrillas regarded each other with ambivalence.

The SLA could indeed become part of a grand alliance of Sudan's marginalized peoples; but Darfurian leaders fear that they will be manipulated -and with good cause. The SLA was catapulted to prominence before it could develop internal political institutions, so that it is an amalgam of village militias and rural intellectuals marshalled by indigenous warrior tradition and the discipline of former Army NCOs. The Fur and Zaghawa wings have often disagreed; and on one occasion even fought each other.

The origins of JEM are even more controversial. The leadership is drawn from the ranks of Darfurian Islamists, widely believed to have received funds from Islamists abroad. In contrast to the amateur public relations machinery of the

SLA, JEM runs a sophisticated political bureau. JEM's roots lie in the fragmentation of Sudan's Islamist movement in the late 1990s, as the twin dreams of national development as an Islamic state, and the emancipation of all Muslims as equal citizens, disintegrated into internal squabbling. The implosion of the Islamic project was clear when, in December 1999, President Omar al Bashir dismissed the Government's eminence grise, Hassan al Turabi, sheikh of the Sudanese Islamists, and later put him in jail. Darfur's Islamist leaders were already disaffected.

Handicapped by the latent Arabist racism of the leadership, which hails, as it always has, almost entirely from Khartoum and the Middle Nile Valley, few Darfurians had risen to the top ranks of the Government or the Civil Service. A clandestine "Black Book", which appeared in Sudan at this time, documented the racial and regional domination of the Sudanese state by those drawn from riverain Arab groups.

There are many conspiracy theories concerning the origins of the SLA and JEM, but Prunier's account -that the Darfur rebellion emerged as a direct consequence of a memorandum of understanding between Garang and Turabi in 2001 -is among the unlikeliest. Putting forward such a claim requires strong supporting documentation, of which Prunier provides none. The critique in the Black Book was aimed, in fact, at Turabi as well as Bashir.

Following the 1999 split and Turabi's imprisonment, President Bashir and his lieutenant, Vice-President Ali Osman Taha, relied increasingly on their own kinsmen, security officers and Islamist cadres drawn from precisely the same Nile Valley tribes fingered in the Black Book. Alarmed at its haemorrhage of support in Darfur, Khartoum's security cabal turned to one of the few senior military figures from Darfur, General Abdalla Safi el Nur of the Ereigat Rizeigat, who responded by putting his kinsmen into key local security posts.

The alliance between Khartoum and the Saharan Bedouins is one of convenience.

Accustomed to seeing Sudan through an "Arab vs African" lens, many observers have missed the fact that there is more than one kind of Arabism at work: the riverain Arabism of Bashir and Taha, coloured by the Islamic movement's orientation to Arab civilization, is a far cry from the Koreishi beliefs of Acyl's Bedouin acolytes. Khartoum's ruling elites regard the Darfur Arabs as no less backward than their non-Arab neighbours. True adherents of the Koreish ideology reciprocate by dismissing the riverain tribes as half-caste "Arabized Nubians".