It is not cynical to say that there is almost nothing new in Gordon Brown’s “long-term and comprehensive framework” for Britain’s role in Afghanistan. The problems are so difficult that there are few answers; the obvious ones have been tried and discarded, and the remainder are variations on the least bad, reworked in the light of six years’ painful experience.

Of necessity, the Prime Minister’s account yesterday was a reassertion that Britain’s role will last for decades, rather than a solution. His suggestions are reasonable, but the language of “frameworks” pretends to find order in a conflict that has resisted it. Britain’s engagement in Afghanistan has more popular support than that in Iraq, but in private officials convey frustration and anxiety at the predicament: taking on more responsibility for a conflict without a visible exit.

The one really new item in Brown’s framework was the proposal that the Afghan government should talk to Taleban who might be won over. But President Karzai has been doing this for a year already, disconcerting British officials who were not sure whether to endorse these tactics.

It is right to do so. President Karzai knew that his faltering grip would fail completely if he did not persuade local leaders to back him. In the south, that means Taleban. The biggest political problem is that even though Mr Karzai himself is a Pashtun, his government is dominated by northern Tajiks, and the south’s Pashtuns feel shut out.

British officials say that Afghans tell them they have persuaded thousands of Taleban to back Mr Karzai in recent months. If true, that is a sign that the paralysis of the south can be broken.

Mr Brown, in announcing that Britain would offer £450 million in development aid and “stabilisation assistance” between 2009 and 2012, has not radically increased support. It remains below that for Iraq, even though Afghanistan has more people, no oil, and is much poorer. But the pledge recognises, as British efforts on the ground finally do, that Afghanistan is an intertwined challenge of political and social development, of which the military is one strand.

There will be no new troops, Mr Brown said, even though the future support of other Nato members cannot be assumed. British forces will remain at about 7,800, although they will get some more patrol vehicles and helicopters. Britain wants the Afghan army to take a bigger share, but it has hoped that for six years.

The capture of Musa Qala, a Taleban stronghold, on Tuesday will recharge the antiopium battle in Helmand province, now the world’s factory; so will the remarks to Congress by Robert Gates, Defence Secretary, criticising the US’s past fondness for aerial spraying. Without providing alternative livelihoods, it drove farmers to the Taleban, he said. The US and Britain now agree.

But six years of new schemes have only seen the crop get bigger. Britain’s hope, having tried everything else, is that general development will erode the incentives to grow poppies.

Britain’s sensible targets for Afghanistan, officials say quietly, are to stop it being a shelter for al-Qaeda and to “take it off the worry list”, even if it is then left bumping along the bottom of the world’s development charts. Achieving even those pared-down goals could take decades.

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