The US surge has almost run out of time – and it isn’t even complete. In military terms, President Bush’s decision to pour more troops into Iraq has had some success, if you don’t judge it by car bombs, which continue to kill dozens in Baghdad.

The only reason for it was to buy time for Iraq’s Government to get a grip – and it hasn’t. Now Congress wants deadlines for getting out, the White House has boxed itself in with self-imposed benchmarks and Gordon Brown, if Prime Minister, is likely to take a brisk view of Britain’s obligations.

In short: after five months, the surge is probably about halfway through, and the Iraqi government has wasted all of that time.

It was always risky to call the manoeuvre a “surge”, implying a climactic rush that would decide the conflict. When the White House rejected the Baker-Hamilton report’s recommendations for withdrawal, and decided to give military effort one last try, it portrayed it as a huge influx of force. The reality of the deployment – as military commanders pointed out in January – has been slower. One brigade (between 4,000 and 5,000 troops) has arrived a month, roughly; in total, three are there, one is on its way and the last will come in June, taking the total from about 135,000 to about 160,000.

Commanders argue – with some justice – that the success should not be measured by car bombs, which are among the easiest form of lethal disruption for the insurgents. But under what is known formally as the “Baghdad Security Plan”, reprisal killings have gone down, officials claim. There are signs that tribal leaders in the rural areas are turning on al-Qaeda members from outside Iraq, particularly in Anbar province, – although this is a phenomenon that officials have claimed to have discerned before, to no steady effect.

US forces are still stretched, to the point where the use of a whole brigade to guard the 100-odd supply convoys a day from Kuwait to Baghdad may be in question. Britain’s decision to ratchet down its forces in Basra – a unilateral decision in all but name – has provoked more than irritation in the US command, where it is seen as adding to the risk in the south. If violence there soars as Britain leaves, the US hopes that Iraqi forces will fill the gap – but that will take them from elsewhere.

The surge is not useless, as critics have charged, but it was never more than a means to an end: buying a bit more time to enable Iraqi government and security forces to improve. The army is better; the police, a bit; the Government hardly at all.

The US’s formal position is that Nouri al-Maliki, the Prime Minister, would curb the sectarian violence if only he could, but it knows that this may give him too much credit. The new ambassador, Ryan Crocker, is putting more pressure on him behind the scenes than did his predecessor, the much-lauded Zalmay Khalilzad.

But when Western officials joke that you have more need of your personal security guards in the corridors of the Ministry of the Interior than outside on Baghdad streets, there is no way to avoid the point that the Government is Iraq’s biggest problem.

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