Operation Forgotten: Two years after the fall of Kabul, a liberated people feels let down by empty promises

While the capital is protected by a 5,700-strong International Security Assistance Force (Isaf), under Nato's control, much of the rest of the country is in turmoil.

Observers say regime change has no more brought an end to conflict in Afghanistan than in Iraq. Indeed in Afghanistan there are now two conflicts: a continuing war pitting the US-led coalition against the remnants of the Taliban and al-Qaida; and a flickering civil war, which the coalition's invasion interrupted.

In recent months Afghanistan has seen its worst violence, on both fronts, for nearly two years.

Hitting-and-running into the south from their safe havens in Pakistan, the black-turbaned Taliban are rallying. American officials report more attacks on the coalition's 11,500 troops in the past three months than the previous 12.

A recent battle in southern Zabol province featured 200 Taliban fighters.

On the mosque doors of Kandahar, the Taliban's former stronghold, edicts forbidding "moments of happiness and other occasions containing music" appear overnight. The Taliban's white flag flutters in outlying villages.

The Taliban have reason to celebrate. When they ambush coalition troops, they invariably come away bloodied. But with a new and repellent tactic, they appear to be scoring a major hit. In March, Taliban fighters shot dead an El Salvadorean Red Cross worker in southern Oruzgan province. In the past three months, 12 local aid workers have been murdered, causing most agencies to withdraw from southern Afghanistan.