As the defence ministers of Nato meet in Vilnius, and Condi Rice and David Miliband descend on Afghanistan as part of their effort to shore up the Nato campaign in the country, someone ought to be asking the question: "What the hell is a North Atlantic alliance doing in a north Asian country at all?"
That is not the same question, although inextricably linked, with the question of whether we, the Brits or the Americans, should be there still or getting out of the morass. Nor is it the same question of whether the current spat between America and its European allies over troop deployments and numbers is a defining point in the alliance or not. But it is to ask whether Nato, the most successful military alliance since the Second World War, is the right organisation for this job, and indeed, whether it can survive the strains that the Afghan occupation is putting on it.
For, make no mistake, that is what the North Atlantic Treaty Organisation has now got itself involved in. When it was first decided to go into Afghanistan and to use Nato as the military command to do it, the case seemed obvious enough. The US had been attacked, it wanted to retaliate as head of an international coalition, its allies in Europe were anxious to show willing, and the political and military heads of Nato itself were keen to establish a new "out-of-theatre" role for an alliance that had lost much of its meaning with the end of the Cold War. Add to that the fact that the institution had a tried and tested command system, and a Nato force appeared just the ticket.
Maybe it was in the initial stages, or maybe someone should have asked at the beginning whether the whole concept of "out-of-theatre" ventures was right for an alliance that had plenty on its plate in the Balkans. But nobody did think about those questions because all the pressure was on to do something in support of the US after 9/11, and Nato seemed convenient as an answer.
But it isn't any longer. What might have seemed a relatively straightforward military venture to overthrow a government and rid the country of al-Qa'ida and its protectors, the Taliban, has now taken on a quite different hue. Having forced regime change, Nato is now there as occupiers, charged with not just fighting the resurgent Taliban, but ensuring security, rooting out drugs production and supporting local civilian rulers whom the alliance favours and removing those it disapproves of.
When President Karzai rounded on the British actions in Helmand recently and rejected Britain and America's candidate for the post of UN representative in Afghanistan, his objections were treated as just the outpouring of a local politician fearful of the loss of his own power. He should have been listened to. What he was saying was that Britain's intervention to remove the local governor – however unpleasant and corrupt he may have been – had changed the rules of the game.
If the object of the exercise was to defeat the Taliban, then the Western alliance should have kept with the local chieftains Kabul knew could manage security in a country where central control barely extended beyond the capital. Once we started to intervene in local politics because of the Western desire to suppress the opium trade and to create a "clean" democracy in its own image, and once we decided to impose a UN representative tasked with ordering political governance in the country, then you made the West part of the political game not an umpire of it.
The argument over the rightness or otherwise of local warlords in Afghanistan is a real one. But Karzai's central point is right. Nato is now there as an army of occupation, tasked with reshaping the country, not a military venture dedicated to seeking and destroying a defined enemy. If this is what we want – and that is what Rice and Miliband seem to be seeking on their latest visit to the country – then let us be honest about it.
Whatever the objectives, however, Nato is the wrong instrument to achieve it. The row over troop commitments in Germany, as in Canada, has shown there isn't the democratic support for a foreign venture such as this among the public of the alliance. And understandably so. Nato has quite enough problems with keeping together in the Balkans and deciding who should join it from the former Soviet Union (it's in the mad position at the moment of having a Hungarian former spy, trained by the KGB in Moscow, acting as chairman of its security committee) without looking beyond its own natural borders.
Last week a group of former top-ranking generals in the organisation produced a paper arguing that the alliance needed to assert a right of first strike if it was to attain its new role of global policeman. God help us all if they should gain a hearing in Brussels, or in Washington. This is nothing to do with Nato and it should have nothing to do with it.