“NOTHING’S happened for five days now,” Major Dennis Grimsley remarked as he mounted his Humvee to escort a convoy of Iraqi troops through western Baghdad.

His mission was simple enough. A three-vehicle American patrol was to accompany four lorryloads of Iraqi soldiers from the 3rd Muthana Brigade to relieve another company located at an observation post just east of Abu Ghraib. The convoy set off down Baghdad’s highway west, the main arterial route for insurgents entering the capital from Anbar province.

Kitted out in surplus US uniforms and touting Kalashnikovs, the Iraqis peered over steel plates welded to the sides of their Nissan trucks towards a drab vista of two-storey shanty-town houses, mud, wire and garbage.

“Damn, they’re going slowly,” Major Grimsley’s driver muttered. “We’ll catch an IED (improvised explosive device) at this rate.”

The bomb exploded in an instantaneous eruption of black smoke and shrapnel, throwing a tombstone chunk of concrete across the road ahead of us a second too late to catch the last lorryload of Iraqi soldiers and just too early to hit Major Grimsley’s Humvee.

As the American vehicles lurched to a halt, their gunners scanning the surrounds for insurgents or a follow-up ambush, the Iraqi troop lorries hightailed it into the distance.

The same moment, on the opposite side of the highway, a construction convoy drove into view, escorted by a masked team of Iraqi contractors spraying the area with machinegun fire. Amid the mayhem, the message was clear: it will be a long time before Iraqi security forces can provide a credible alternative to the coalition.

More than 100,000 Iraqis have already been recruited to the new Iraqi Army, a figure intended to reach 135,000 this year. On paper at least they already dominate operations in much of the country. More than 60 per cent of Baghdad is already the preserve of Iraqi forces, allowing US troops to move elsewhere and, potentially, home.

As the regular US troops pull back, they hand the fight over to Iraqi forces accompanied by small teams of US advisers such as Major Grimsley.

As well as training and mentoring the Iraqis, the advisers co-ordinate the supply of the coalition assets they lack, including air cover, engineers and medical evacuation: a template that is expanding by the day throughout Iraq, and is likely to set the pattern of the war for years ahead.

Both Iraqi and US soldiers are quick to point out the very real benefits of having indigenous troops out on patrol. Thanks to their ability to understand local people, gain intelligence and spot outsiders, there has been a 30 per cent rise in tip-offs from Iraqi civilians in the Muthana Brigade’s area since December.

But critics of a hasty US withdrawal contend that the fledgling Iraqi Army will fall apart unless it is carefully supported for a long time to come, and even the most cursory examination of the Muthana Brigade during a two-day embed by The Times suggested that it remains crucially reliant on US support.

The brigade is due to take full responsibility for the area by the spring, but its logistics are a shambles.

One typical battalion had a third of its vehicles awaiting repair, with no means of acquiring spare engine parts. The cadre of Iraqi NCOs appeared to be virtually non-existent. And the predominantly Shia soldiery served under no contract. If they wish to go home they are free to leave: desertion does not exist as an offence. The brigade has had 22 members killed and 70 injured during the nine months it has been operating in the area.

“If they get hit hard you find probably 30 or 40 just don’t turn up to work next day,” one US adviser said. “They usually come back though, a few days later.”

The brigade is nearly 50 per cent understrength, and the loyalty of most of its 1,600 troops is secured largely by their $300 (£170) monthly pay packet.

For the lorryload of Muthana troops who sped away after the bomb attack the concept of “support” is apparently a one-way affair. “I mean, they might at least have radioed to see if we were all right,” said Major Grimsley, contemplating the fruit of his ten-month relationship with the Iraqis.

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