Mr Bush has tried to give himself room to manoeuvre by commissioning three reviews of US policy: the Iraq Study Group, a bipartisan panel headed by James Baker, the former Secretary of State, whose report will be published on December 6; a Pentagon analysis; and a report by the National Security Council. These are looking at three basic options, which the Pentagon has summarised as “Go Big, Go Long and Go Home”.

There are no new ideas and no formula for success — or even for avoiding failure. Any way forward is likely to incorporate elements of all three.

Go Big?

Doesn’t that mean more troops?

Yes, but only temporarily. The idea would be to increase US troop levels by tens of thousands to suppress violence in key areas, particularly Baghdad.

Advocates Republican Senator John McCain and some neoconservatives.

Pros Establishing order would give the Iraqi Government a better chance of reconstructing the country, cracking down on militias and securing a power-sharing deal.

Cons The plan would take pressure off Iraqis to take responsibility for their security, and further inflame anti-US sentiment in the region. Many see it as too little, too late.

Go Long?

Isn’t that just “stay the course?”

In essence, yes. It envisages a renewed focus on training Iraqi forces and a very gradual withdrawal of US troops, while putting on pressure the Iraqi Government to control militias, strengthen security forces and reach political agreements.

Advocates President Bush, Vice-President Cheney and senior US military leaders.

Pros Gives the Iraqi leadership time to stabilise the country and reach power-sharing agreements.

Cons Has so far failed. Nouri al-Maliki, the Prime Minister, has less control of Iraq than he had when he took office in May, and the option has little support in the US.

Go Home?

Isn’t that cut and run?

It is more cut and jog. An immediate withdrawal is not an option, even for most Democrats.

A phased withdrawal, beginning as early as next June, would put pressure on the Iraqis to deal with the violence themselves.

Advocates Most Democrats and some senior Republicans.

Pros By making clear that a withdrawal is imminent, the Iraqis would have no option but to take responsibility for security and reach a political consensus.

Cons Iraq could slide into full civil war and become haven for terrorists. Such a move would also be viewed in Iraq and across the region as a US surrender.

Are there other options?

Yes. Partition Iraq into three semi-autonomous Shia, Sunni and Kurdish regions. The White House calls this a non-starter.

Alternatively, the US could pick a winner between the Shias and Sunnis, and back an Iraqi “strongman” who will focus on stability rather than democracy.

What’s all the talk about asking Iran and Syria for help?

The Baker commission is widely expected to advocate a diplomatic initiative or a regional conference to enlist the help of Tehran and Damascus.

Advocates Tony Blair, James Baker, Robert Gates, the new US Defence Secretary and the State Department.

Opponents Mr Bush, Mr Cheney and Israel.

Pros Iran and Syria do not want prolonged civil war in Iraq and they have more clout in region than the US does.

Cons The US would be dealing with pariah states — one a member of the original Axis of Evil — and would be increasing Iran’s influence in the region at a time when it is trying to curb Iran’s nuclear ambitions.

Is Iraq in a civil war?

Many US military analysts and politicians now say yes. NBC news on Monday used the term for the first time. Two-thirds of Americans call it a civil war. Mr Bush continues to call it “sectarian violence”.

What is the US likely to do?

Mr Bush is still the commander in chief so technically the decision is still his. He clearly favours the “Go Long” option, and is against talking to Iran and Syria.

But with the Democrats in control of Congress and the war supported by 30 per cent of Americans, his power to act is significantly constrained.

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