Weeks after the Bibi Fatima girls' school was rebuilt, arsonists came and burned it down.
"We don't know if it was burned because it was a girls' school or because the US built it," an American soldier said of the incident in the northern Afghan province of Kunduz. "But we started right away to build it again."
In Afghanistan these days, the US military is not just a combat force fighting Taliban and al-Qaeda remnants.
It is increasingly involved in providing humanitarian assistance, a "shift of emphasis" underlined on a recent Kabul visit by US Defense Secretary Donald Rumsfeld.
Three US army Provincial Reconstruction Teams (PRTs) have deployed this year in the towns of Gardez, Bamiyan and Kunduz. The British army is likely to deploy a fourth next month in Mazar-i-Sharif, with an announcement expected within days.
Islamic extremists are not the only ones annoyed. The initiative has also come under fire from aid agencies concerned it will blur the line between humanitarian workers and soldiers, and put their staff at risk.
"They have come with the best intentions, they really want to do good," said Rafael Robillard of aid coordinating body ACBAR. "But it is creating a lot of confusion in the minds of people."
Aid workers say Afghanistan in 2003 must not become Somalia in 1993, when US soldiers deployed to protect food deliveries to a famine-stricken land ended up embroiled in clan feuds.
When Somalis rose up to throw out the US military, foreign aid workers were forced to flee too. Schools and hospitals built by foreigners were destroyed by angry mobs.
In Afghanistan, the Taliban is already targeting aid workers -- two have been killed in the last six weeks. "Aid workers in uniform" could make a bad situation worse.
"When they go into a village offering assistance in uniform, it communicates a message that all foreigners are part of the military and political campaign to stamp out the Taliban," said Paul O'Brien of Care.
"That does untold damage to our relationships and our long-term reputations as non-governmental organisations."
PRTs involve between 40 and 100 personnel and aim to build schools and clinics as well as repair roads and bridges.
Rumsfeld said he hoped they could contribute not just to improving security but also to the lives of ordinary Afghans. There is also a political message, for PRTs aim to reinforce the government's standing in provinces where it has little sway.
Concerned not to duplicate efforts, PRT officers insist they will only do projects aid agencies will not or cannot undertake, especially because of security fears. They have no desire for the line to be blurred any more than it is already.
"We understand the seriousness of that concern," said US Major Kevin Lanigan. "The fact that we are working everywhere in uniform is a very important piece of avoiding this blurring."
At the UN, officials hope PRTs can contribute to security, even if they fall far short of the countrywide peacekeeping effort the UN is seeking.
Lanigan is keen not to raise expectations too high.
Small groups of soldiers attached to PRTs will focus primarily on guarding their compounds, he says. But with the ability to call in air strikes or reinforcements if they need to, even a small US presence can have leverage.
"The PRT is not a sizeable, powerful peacekeeping force. It doesn't have the ability, it doesn't have the mission to enforce the peace by being the largest force in the area," he said.