THE former American secretary of state Colin Powell has revealed that he spent 2½ hours vainly trying to persuade President George W Bush not to invade Iraq and believes today’s conflict cannot be resolved by US forces.

“I tried to avoid this war,” Powell said at the Aspen Ideas Festival in Colorado. “I took him through the consequences of going into an Arab country and becoming the occupiers.”

Powell has become increasingly outspoken about the level of violence in Iraq, which he believes is in a state of civil war. “The civil war will ultimately be resolved by a test of arms,” he said. “It’s not going to be pretty to watch, but I don’t know any way to avoid it. It is happening now.”

He added: “It is not a civil war that can be put down or solved by the armed forces of the United States.” All the military could do, Powell suggested, was put “a heavier lid on this pot of boiling sectarian stew”.

The signs are that the views of Powell and other critics of the war are finally being heard in the Pentagon, if not yet in the White House. Robert Gates, the defence secretary, is drawing up plans to reduce troop levels in Iraq in anticipation that General David Petraeus, the commander in Iraq, will not be able to deliver an upbeat progress report in September on the American troop surge.

“It should come as no secret to anyone that there are discussions about what is a postsurge strategy,” said Tony Fratto, deputy White House press secretary, last week.

The surge’s lack of demonstrable success is creating fissures in the Republican party as well as putting enormous pressure on the Democratic presidential candidates to favour a rapid pull-out, which Gates fears could leave Iraq in chaos.

New Mexico senator Pete Domenici became the third Republican senator in recent weeks to break ranks openly with Bush on the war. “We cannot continue asking our troops to sacrifice indefinitely while the Iraqi government is not making measurable progress,” he said. “I am calling for a new strategy that will move our troops out of combat operations and on the path home.”

Speculation is growing that Gates will demonstrate his commitment to withdrawing US forces by moving a combat brigade of up to 3,000 troops out of Iraq as early as October and continuing to reduce their numbers month by month from their current strength of 160,000 to presurge levels of around 130,000 by the summer of 2008.

Gates believes American troop withdrawals are essential to building a cross-party consensus for retaining a presence in Iraq after Bush’s term in office expires. As a former director of the CIA who saw out the cold war in the early 1990s, he hopes to win the same bipartisan support for Iraq that President Harry Truman secured against the Soviet Union after the second world war.

The policy is likely to appeal to Gordon Brown, the prime minister, who hopes to begin withdrawing more British troops from southern Iraq by the end of August.

A senior defence source said it would be possible to reduce the number of American forces to roughly 50,000-70,000 by election day in November 2008. “You are going to have to have some people left behind to provide stability and security for the country and take on the terrorists,” the source said.

The figures are similar to those floated by aides to Hillary Clinton, the frontrunner for the Democratic presidential nomination, although she has been upping the rhetoric against remaining in Iraq in an effort to capture the support of party activists.

According to Powell, the US cannot “blow a whistle one morning” and have all American forces just leave. The former secretary of state has twice met Barack Obama, the Democratic candidate, to advise him on foreign policy. Despite his antiwar stance, Obama supports a phased withdrawal that could leave a “significantly reduced force” in Iraq for “an extended period”.

Defence experts believe it will be impossible to maintain the surge’s high troop levels beyond February at the latest, given the need to rotate and refresh troops. Powell, who served as chairman of the joint chiefs of staff in the early 1990s, said in Aspen that America’s volunteer army was already overstretched. He predicted that Bush would be forced to “face the situation on the ground” and alter course by the end of this year.

Supporters of the surge believe this could send a disastrous signal to the Iraqis. “If we pull out, if we stop this operation now, we will hand Al-Qaeda a terrific victory,” said Frederick Kagan, a military historian at the American Enterprise Institute and an early advocate of the policy.

“The Iraqi government, right now, is a terrific ally in the war on terror. There have been more Iraqis killed fighting Al-Qaeda than in any other nation of the world. The question is, are we going to stand by them?”

The same political fault line runs through the White House between Vice-President Dick Cheney’s office and the State Department – now run by Condoleezza Rice, Powell’s successor – as it did at the start of the Iraq war. Bush has not yet thrown his weight definitively behind one side or the other, but the key difference this time is that the defence secretary is one of the “realists”.

According to Powell: “We have to face the reality of the situation that is on the ground and not what we would want it to be.” He believes that, even if the military surge has been a partial success in areas such as Anbar province, where Sunni tribes have turned on Al-Qaeda, it has not been accompanied by the vital political and economic “surge” and reconciliation process promised by the Iraqi government.

Al-Qaeda, Powell asserted, was only 10% of the problem in Iraq and Nouri al-Maliki, its prime minister, lacked the political will to establish an effective government. After a promising start to the surge at the beginning of the year, 453 unidentified corpses were found on the streets of Baghdad last month, 41% more than the 321 bodies found in January, according to unofficial Iraqi health ministry statistics.

The military gains could prove as fleeting in Anbar as Baghdad. American officers in Iraq believe Al-Qaeda strengthened its hold on the Sunni-dominated region in 2005, when responsibility for security was shifted prematurely to Iraqi forces that were led by Shi’ites and proved incapable of providing protection.

Powell believes that a reduction in US forces will have to be accompanied by talks with Syria and Iran. “You have to talk to the people you dislike most in this dangerous world.”

The general and former joint chiefs of staff added: “Shi’ites will ultimately prevail because they are 60% of the population and their militias can be pretty violent. They will prevail also because they are determined not to be ruled again by the Sunnis.

“The Sunnis are struggling for power and survival and it’s going to be resolved by a test of arms. It’s going to be very ugly.”

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