When historians look back on the past week in Washington, I suspect they will see it as a seminal moment. It was the moment when the president and his party recommitted themselves to an indefinite, decades-long Iraq occupation, and when the Iraq war was formally handed over to the next president, with forces near the maxed-out 2006 level.

The realist and moderate Republicans were essentially defused by the calm, factual demeanour of General David Petraeus, with the key senators John Warner, Richard Lugar and Pete Domenici deferring to the president in the face of the first trickle of good news from Anbar.

Amazingly, the president even got the press to echo the notion that he is actually withdrawing troops, when he is simply maintaining the maximum level compatible with not breaking the US military entirely.

And so, barring something unforeseen, after the surge dies its predicted cyclical death next spring, well over 100,000 American troops will likely be occupying Iraq when the next president takes office.

The argument that won the day is that however deep the current hole, leaving now would create an even deeper one. So they’re digging some more.

For me, the critical exchange evinced a response from Petraeus that, after a recess, he decided to withdraw. Too late. The truth had been blurted out. When staunch Republican Senator John Warner asked him: “Does the [Iraq war] make America safer?” Petraeus replied with admirable honesty: “I don’t know, actually. I have not sat down and sorted in my own mind.”

Who in the administration, one wonders, has?

Let us review the stated objectives of the Iraq war chronologically:

2002: to disarm Saddam Hussein of stockpiles of weapons of mass destruction and create a breathing space for democracy in the Middle East (the WMDs were not there; the breathing space became anarchy).

2003: to allow chaos in order to create a “fly-paper” for every jihadist in the world to come and get slaughtered by the US (“Bring it on!”).

2004: to create a new democratic constitution (achieved on paper, but at the price of creating sectarian voting blocs that actually intensified the ethnic and religious divisions pulling the country apart).

2005: to protect Iraq from a powerful and growing Sunni insurgency and disarm the Shi’ite militias (failed).

2006: to quell surging sectarian violence, target a new and lethal Al-Qaeda in Iraq and restrain the passions unleashed by the bombing of the Samarra mosque (failed).

2007: to prevent genocide and a wider regional war and create enough peace for a settlement in the centre (the surge has reduced violence to levels of summer 2006, and no agreement in Baghdad has been reached).

And so the question becomes: what will the objective of the Iraq war be next year? Given the dizzying succession of rationales presented and subsequently withdrawn by the president and his supporters, the possibilities are many.

Some cynics argue that George Bush is playing a small, domestic game of keeping the ordeal going so that the next Democratic president can be accused of losing Iraq – not him. But this theory, while not totally implausible, does not quite fit with the messianic ambitions of the president and apocalyptic fears of Vice-Presi-dent Dick Cheney.

Other cynics maintain that the abandonment of the Iraq goals of four years ago, and even the more restrained goals of 2006, represents the slow revelation of the real objective: securing Iraq’s oilfields to protect America’s economy. Again, it is impossible to disprove this.

Some defenders of the indefinite occupation argue proudly that energy resources are a good and fundamental reason to hang in. But it is a little too mundane for a man of Bush’s character. It doesn’t quite have the frisson, the bigness of Bush’s signature goals.

My sense is that the point of the war in Iraq, in the president’s mind, is an attempt to quash any and all Islamist tendencies with American military power. The enemy is the right one, but, alas, he doesn’t have enough troops to remake an entire country from scratch and the target of his attention – Islamist ideology – turns out to be particularly resilient in the face of raw military force.

These nuances are now, and always have been, lost on Bush. But even if they were not, he cannot switch gears. It is simply not in his DNA to absorb the lessons of the past few years and adjust – radically – to a new posture.

And so the real and present danger is that by digging in further Bush will not only keep providing Al-Qaeda with the oxygen that American occupation of a Muslim country provides, but will also find himself dragged, willingly or unwillingly, into a military confrontation with Iran. Already last week Fox News reported serious planning for a missile attack on Iran’s nuclear facilities next spring.

The vice-president is eager for another war to scramble what he sees as a weakened hand in Iraq. And the old policy of propping up Sunni powers – such as Saudi Arabia – against Shi’ite Iranian influence is slowly becoming the default American posture again.

The West, in other words, will not only be facing the extremist fringe of Al-Qaeda, but also taking on Shi’ite Islam in a sectarian regional war. If you wanted a policy that both multiplied and empowered your enemies, it would be hard to find a better one.

Maybe this won’t happen. Maybe events in Iraq will turn in a more hopeful direction. I certainly hope so – and in the fog of war it is very hard to see ahead confidently But I see no sure reasons for solid optimism – and much evidence that beneath a small reduction in violence in the face of 30,000 more of the best military in the world, the deeper tensions in Iraq remain as lethal as ever.

Last Thursday, America’s most important Sunni ally – Sheikh Abu Risha – was murdered in Anbar. An oil deal collapsed in Baghdad. And Ramadan began. Just recall that fatal exchange in the Senate last week: “General, does the [Iraq war] make America safer?”

“I don’t know, actually.” I’m afraid I do.

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