Leading article: Can it be the beginning of the end?

The new Government's foreign policy has not changed as much as it should, or as much as Liam Fox, the Defence Secretary, pretends.

Mr Fox, in Afghanistan for a "surprise" visit (and all trips by public figures, including David Beckham, seem to be a "surprise") said that it was not the purpose of the British military presence in the country to ensure that girls could go to school. "We have to reset expectations and timelines," he said. "National security is the focus now. We are not a global policeman.

"We are not in Afghanistan for the sake of the education policy in a broken 13th-century country. We are there so the people of Britain and our global interests are not threatened."

Well, the mission had already been recalibrated by the outgoing Labour government, and the transfer of British troops to American command has been planned for some time. But there is no harm in some symbolism. A new government has the chance to press the "reset" button, and Mr Fox, along with William Hague, the Foreign Secretary, and Andrew Mitchell, the International Development Secretary, have used the opportunity to lower expectations. It was telling that it was Mr Fox who led the recalibration exercise, as he is the most "neo-conservative" of the trio. He has been a muscular interventionist and a staunch pro-American. So it is particularly welcome to have him follow The Independent on Sunday's urging of a less ambitious, and more realistic, policy in Afghanistan.

This newspaper became the first to call, last year, for a phased withdrawal of British troops from combat roles in Afghanistan. We led the growing consensus that our military mission in the country should focus on training the Afghan police and army, special forces operations and sealing the border with Pakistan.

We gave practical expression to the belief that British soldiers are paying too high a price for a mission the purpose of which is unclear, unrealistic and lacking a credible end point. To the extent that the Conservative ministers were signalling their acceptance of this, their Afghan trip is welcome.

Afghanistan needs to be seen, of course, in the context of the "Strategic Defence and Security Review" which the coalition promises in its document published last week. That is the point at which we need to decide to what extent Britain should try to be a "global policeman"; where and when we should intervene militarily, and what our exit strategy should be when we do.

This newspaper supports liberal interventionism when it meets the stringent tests set out by Tony Blair in his Chicago speech 11 years ago. Are we sure of our case? Have we exhausted all diplomatic options? Are there military operations we can sensibly and prudently undertake? Are we prepared for the long term? And do we have national interests involved? We supported the initial action in Afghanistan, but we led the opposition to the invasion of Iraq because we felt it failed to meet those conditions. We now believe that our presence in Afghanistan has fallen victim to mission creep and should be scaled back. Being prepared for the long term should not be mistaken for being sucked into an open-ended commitment.

The complication in all this has long been the policy of Barack Obama, because US forces play the lead role in Afghanistan, and we believe that he has approached the question of how to bring his predecessor's engagement there to a stable and secure conclusion with the seriousness it deserves.

However, we are not convinced that he achieved the clarity of purpose he sought. The military objective of the US-led presence seems to have become focused on not getting blown up or shot at. In which case, we believe that Britain should continue to provide the international force with political support as General Stanley McChrystal tries to increase his forces in order to reduce them. But we should make clear to the Afghans and the Americans that our role in combat operations is coming to an end.

Foreign policy is too important for posturing. Which is why we are not impressed by Ed Miliband and Ed Balls using the Iraq war, rather late in the day, as a gesture in the Labour leadership campaign. What matters is getting the policy right at the time, which is why we hope that the Coalition Government really is going to change policy in Afghanistan and start to bring the troops home, rather than simply engaging in spin.