U.S. troops in Afghanistan are taking on more jobs that look like peacekeeping and nation-building: They're repairing hospitals, schools and waterworks. They set up a medical school. They're going to help train an Afghan army.

Soon, U.S. military advisers may be sent to prevent clashes among feuding warlords, which would give evidence of deepening U.S. involvement despite the Bush administration's reluctance to engage in peacekeeping.

White House spokesman Ari Fleischer made clear Monday that President Bush still wants the military used only to fight and win wars. But he said the United States is talking with allies and considering how to strengthen security forces now inside Afghanistan to keep the country from falling into chaos.

"The United States is committed to the long term of Afghanistan, including its security and safety," Fleischer said. "I think it is also fair to say that it's not going to be an easy process, and it's not going to happen overnight."

The U.S. commander in the war, Gen. Tommy Franks, said options include expansion of the 4,500-person, British-led international security force, which now operates only in the capital, Kabul. Franks ruled out making peacekeepers of the U.S. troops.

"What we are prepared to say is that we want to do something that will increase security" beyond Kabul, Franks said. He called the security situation "murky and troublesome."

The sticking point is that U.S. allies have been unwilling to commit to a larger peacekeeping force unless the United States also commits more troops, said Ivo Daalder, an analyst at the Brookings Institution.

In general, U.S. officials agree that helping create a national Afghan army is the best long-term solution. The problem is how to prevent battles until then.

Defense Secretary Donald H. Rumsfeld clearly favors waiting for the national army. But at least one high-ranking State Department official has indicated more peacekeepers may be needed.

On Sunday, the U.S. special envoy to Afghanistan, Zalmay Khalilzad, told reporters the United States may send military advisers to act as referees among rival warlords until a national army can be formed. Alternatively, the task could be given to special forces troops already there.

"We are worried about the multiple armies," Khalilzad said of the warlords and their armed men. "There is a danger of multiple armies going to war."

Despite his preference for training an army, Rumsfeld last week refused for the first time to rule out an American role in keeping order in Afghanistan. Among possibilities her mentioned was the dispatch of sending up to 30,000 U.S. soldiers to "police the whole country."

"If it turns out it (training an Afghan army) can't be done as rapidly or as effectively or in a way that is cost-effective, then clearly we would do something else," Rumsfeld said.

Already in Afghanistan, many U.S. troops perform duties that resemble peacekeeping and nation-building. Special forces troops, in particular, spent much time after the Taliban's fall analyzing and addressing the country's immediate needs, said Col. Rick Thomas of U.S. Central Command.

About 225 Army civil affairs troops now are helping to rebuild damaged schools, hospitals and water supplies, Thomas said.

They also work with the international peacekeeping force to set up a medical school in Kabul, including obtaining equipment and books, and to organize food-for-work programs around Herat and assist a group that helps Afghan widows earn money sewing.

The United States also has agreed to help train the national army.

"The little secret is that the U.S. Army, and even the Marines, this is what they do, engage in nation-building activities like training armies or humanitarian relief," said Brookings' Daalder. "That's what Special Forces do 99 percent of the time."

The bulk of the 4,000 U.S. troops in Afghanistan are either searching for al-Qaida leaders, guarding detainees or providing security to U.S. troops.

Douglas Feith, Rumsfeld's undersecretary of defense for policy, said the Bush administration shies from the term nation-building, even for activities like building schools or training an army.

"We don't like the connotation of nation-building because it implies an ambition, which we don't have, to exercise a degree of control," Feith said. "We're not trying to shape the politics of other people's countries."