WHAT is Britain doing in Afghanistan? The death of the first British soldier in fighting since the operation was expanded should make everyone take a hard look at that question. The Government says it has answered it, but it hasn’t.

The first military fatality cannot be a surprise. In April John Reid, then Defence Secretary, told troops that they faced “massive risks” in deploying to Helmand province; the evident strength of the Taleban has confirmed his prediction.

But it is the slipperiness of the definition of the mission that should create alarm. If that does not become clearer, Britain’s deployment in Afghanistan will look like Tony Blair’s excuse for beginning to leave Iraq, poorly disguised with wisps of 19th-century colonial memory and 21st-century development jargon.

Britain now has more than 3,300 soldiers in Afghanistan, mainly in the Taleban-and- opium stronghold of Helmand in the south. Britain took control of Nato’s International Security Assistance Force (Isaf) on May 4, and the 9,700 force will eventually grow to 16,000.

At the same time US forces will be cut by 3,000, leaving 20,000 under a separate chain of command.

This changeover has coincided with an upsurge in Taleban violence, with coalition forces drawn into clashes. The Afghan Government and the coalition have gone to great lengths to portray this violence as temporary. Abdur Rahim Wardak, the Defence Minister, said last week that the Taleban had stepped up attacks to “take advantage of this time of transition”.

Maybe. But there are plenty of reports about how the Taleban, chased out of Kabul, and government, in December 2001, has grown again as a real force in the running of the southern provinces. In which case, what is the British mission?

The Isaf forces are supposed to be keeping the peace in order to let the Government develop its security forces, get a proper grip on the provincial government and set about providing water, schools, roads and all the other building blocks of the development dream. Britain has called this “reconstruction” but the better word is “construction”, for this area never had these services.

But the Kabul Government, from behind its security barricades, has taken those steps only in the most faltering way. Its grip on provincial government looks barely better than a couple of years ago when President Karzai was persuaded by the US and Britain to depose — or rather reshuffle — some of the worst warlords and chieftains masquerading as governors. So Nato forces are inevitably drawn into problems that should be solved by Kabul or the province: tribal wars, water and land rights, and feudal conflicts going back centuries.

It is not part of the mission of British troops to go “looking for trouble”, officials have said. But it is hard to see how they can avoid it, given that their aims conflict so directly with those of the Taleban.

Above it all hovers the fog of the policy on drugs. British troops do not have an explicit anti-narcotics role. But the coalition’s hopes for Afghan democracy depend on removing power from the drug barons. Britain has looked coolly on the US enthusiasm for spraying the crops, preferring to talk of persuading farmers to switch to other crops — an admirable tactic, except that no other crops approach the same value.

Compared with Iraq, Afghanistan has been peaceful in the past four years, but that is misleading. It lacks Iraq’s educated population, oil wealth and water, and its feudal divisions are at least as deep as Iraq’s Sunni-Shia rift.

The expanded role Britain has chosen to take on in Afghanistan is more poorly defined than that in Iraq, and even more open-ended.

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