He is credited with taming the violence in Iraq, rewriting American counter-insurgency strategy and salvaging the reputation of the US military.

When General David Petraeus steps down today as the commander of US forces in Iraq however, he will have little time to savour the plaudits from fellow soldiers and the Bush Administration.

Instead the politically savvy paratrooper will swap the Iraqi frying pan for the Afghan fire. General Petraeus will take command of all US forces in the Middle East and Central Asia and with it the unenviable task of turning round the increasingly desperate fight faced by US and Nato forces in Afghanistan — a war that he conceded was “headed in the wrong direction”.

The general was hailed as “the hero of the hour” by the US Defence Secretary, Robert Gates, for appearing to have pulled Iraq back from the brink of civil war after he successfully oversaw a surge of 30,000 extra US troops into the country.

When General Petraeus took on his role almost 19 months ago Iraq was heading towards sectarian civil war. “The violence was horrific and the fabric of society was being torn apart,” he said.

The general developed an approach to counter-insurgency and was responsible for expanding combat outposts — platoon-sized bases in areas where insurgents previously had freedom of movement. He said: “You can't secure the people if you don't live with them.”

It remains to be seen if he can have the same impact in Afghanistan, where violence has increased since the Taleban were overthrown in 2001.

The outgoing Bush Administration and both US presidential candidates promised to send thousands of US reinforcements to the country, although the nature of the conflict was very different.

“We've got a situation in Afghanistan where clearly there have been trends headed in the wrong direction,” General Petraeus said. “Military action is absolutely necessary but it is not sufficient.”

“Political, economic and diplomatic activity is critical to capitalise on gains in the security arena,” he told the BBC.

At a ceremony in Baghdad today the general will hand command of US troops in Iraq to his former deputy, Lieutenant-General Ray Odierno who, on acceptance, will be promoted to general.

General Petraeus gave warning that US troops still faced a “long struggle” to rid Iraq of violence. Despite violence being at its lowest since 2004 the volatile security situation was illustrated yesterday by two simultaneous suicide bombs in Baghdad and another in Baquba. The attacks claimed 32 lives.

As a deputy to General Petraeus, General Odierno was one of the chief architects of the surge and first proposed it to a resistant Pentagon in 2006.

“Just as important as the surge was the change in our tactics: techniques and procedures got us back out in the neighbourhoods,” General Odierno said at the end of his 15-month tour in March.

At 6ft 5in the large frame and shaved head mark out General Odierno as a military man. He served in the Gulf War in 1991 and was a deputy commander of an army task force in Albania during the Nato air war over Kosovo in 1999. His greatest achievement was when his troops captured Saddam Hussein.

During this time he was criticised for alienating much of the population. It is believed that his troops paid little attention to hearts-and-minds operations, often under-taking massarrests and cordoning off whole villages, alienating Sunni villagers.

One of the first tasks for General Odierno will be to oversee the scaling-back of America's 146,000 troops. By January 8,000 would have left the country and further cutbacks are likely as focus shifts to Afghanistan.

Another potential problem is that the Sons of Iraq, a Sunni militia group paid by the US to help to keep the peace and hunt al-Qaeda, could be disbanded when the Shia-dominated Iraqi Government takes control of it. If disbanded, the former insurgents could go back to fighting US and Iraqi forces.

Petraeus’s command

2007

January 11 Surge of US troops announced

February 10 David Petraeus appointed commander of the Multinational Force in Iraq

May 126 US deaths, most in one month since 2004

August The Shia cleric Moqtada al-Sadr calls for ceasefire

2008

February 22 Al-Sadr extends ceasefire

April 8 Petraeus describes “significant but uneven” progress in Iraq

July Petraeus confirmed as head of Central Command in Iraq, month ends with 11 US deaths, lowest ever

Source: agencies

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