The least one can expect of a president who prolonged Afghan suffering by ordering a surge of troops to finish the job, is that he has something that could be dignified with the name of an exit strategy

It is disingenuous to claim, as Barack Obama did at the Nato conference in Chicago, that in two years, when US troops have ended their combat role in Afghanistan, the war "as we understand it" will be over. First, the US military has never understood what it was doing in Afghanistan, still less whom it was fighting, as one of its fallen stars, General Stanley McChrystal, admitted last year. He never resolved the contradictions inherent in conducting a counter-terrorist campaign and building a viable state, without which territorial gains were worthless. The state-building agenda has been quietly shelved since Gen McChrystal's days, but this does not lessen the failure. Second, with Nato bolting for the exit door, it is not within Washington's power to declare the war over. That can only be done by Afghans who see that peace has come.

The least one can expect of a president who prolonged Afghan suffering by ordering a surge of troops to finish the job, is that he has something that could be dignified with the name of an exit strategy. But, as Henry Kissinger acidly observed, the exit strategy has become all exit and no strategy. He is right in more than one sense. On the tactical level, the Nato conference finessed the French insistence on pulling its troops out this year, with private assurances that their combat mission has stopped anyway, that France may continue its training mission, and that it will take longer than the end of this year to withdraw most of the 3,200 troops and their kit. But these do not address the substance of the argument, which is as valid in Mr Obama's America as it is in François Hollande's France: that no one can see what the continued presence of foreign combat troops is doing.

The picture darkens further on the strategic level. Speed is now of the essence: war fatigue (a poll conducted in April showed that 69% of Americans wanted their troops out now), the imminence of the US presidential election, increasing Afghan hostility to the international military presence, the rise of "green on blue" shootings this year, the lack of mutual trust between Hamid Karzai and Mr Obama all point in the same direction. If the US military failed at the height of the surge in rebuilding infrastructure through its provincial reconstruction teams, the idea that the opposite force will produce the same result – that the prospect of a withdrawal of US troops will force a weak state to become stronger – is just as fanciful.

The more rapidly 2014 approaches, the sharper the contrast will become between airy aspiration and gritty realities on the ground. And yet the prospects of an "irreversible" transition from a foreign-led combat mission to an Afghan one depend more than ever on results, not statements or hopes. Mr Karzai may claim that soon 75% of the population will come under the protection of local forces, but the ability of Afghan forces to stand on their own remains unproven theory rather than established fact. Those are the words of Ronald Neumann, a former US ambassador in Kabul, not ours. Doing nothing to staunch the combat while troops are being withdrawn, the exit strategy amounts to little more than firing the same volley of bullets through a longer barrel. On this point alone, the statement issued by the Taliban is right: one step forward, two steps backward and no clear strategy for a political solution. It is only when the Taliban commanders held in Guantánamo Bay are handed over, that the next paragraph in their statement can be tested: that if the occupation of Afghanistan is ended "Afghans can … reach a resolution regarding their country".

Getting from a jihad run in the name of an Islamic emirate to a power-sharing agreement with an Afghan government that retains control of Kabul and most of the country will require negotiating resources that no Afghan leader has lived long enough to accomplish. The Taliban show no signs of being forced to the negotiating table. And the US shows no signs of abandoning the good fight, even though it has long since turned bad.