U.S. officials have concluded after 10 months of war that the combat mission of U.S. conventional military troops in Afghanistan is largely over and that whatever fighting remains is likely to be carried out by small numbers of Special Forces troops and CIA operatives.

This new phase represents a sharp shift from the U.S. military posture of last spring, when thousands of regular U.S. infantry troops fought al-Qaida positions in the Shahikot Valley and then conducted sweeps along the Afghan-Pakistani border.

U.S. Special Forces and Afghan allies conduct inventory on a massive arms cache they found last week on the border of the Paktia and Paktika provinces in Afghanistan. Some of the weapons will be used by the new Afghan National Army, which the U.S. forces are helping to train. Sources close to the Pentagon say the U.S. war on terrorism in Afghanistan will start to rely more heavily on Special Forces and less on regular infantry.

“The war is over militarily for the moment,” said a senior U.S. military officer involved in the fighting.

Now, officials said, the Afghan war is reverting to the methods used last October and November, when small teams of Special Operations troops spotted targets for bombers and worked with Afghan fighters. These units, which are trained to conduct covert raids and to work hand-in-hand with the CIA and foreign militaries, are focusing on small-scale efforts to track down Taliban leaders in southern Afghanistan and al-Qaida fighters who have fled across the border into Pakistan.

“It is now primarily a war in the shadows, as it should be,” said a U.S. military expert on such operations.

These sources stressed that the situation in Afghanistan is fluid and unpredictable and that conventional troops could again take a central role if the new government in Kabul isn’t able to establish its hold on Afghanistan. The uncertain state of President Hamid Karzai was underscored Saturday by the assassination in broad daylight of Abdul Qadir, one of his three vice presidents.

Political role for soldiers

But the intention now is that almost all of the 7,000 U.S. soldiers in the country should increasingly play less a purely military role and more a political one, in effect acting as a reassuring presence to deter challenges to the Karzai government and to the international peacekeeping force in Kabul.

The conventional troops are unlikely to be withdrawn soon, officials say. Rather, units from the 82nd Airborne Division are deploying to Afghanistan to replace those from the 10th Mountain and 101st Airborne divisions, and such troops are likely to be required for years to come.

“It’s a deterrent and response force,” the senior defense official said. “The peacekeepers wouldn’t be there without them.”

The shift in approach hardly means that Pentagon officials think their antiterrorism efforts in Afghanistan are finished, or even becoming much easier to prosecute. Indeed, many defense experts, including some who have consulted with the Pentagon on the conduct of the war, say the lull in fighting offers an opportunity to assess the U.S. approach and make potentially crucial adjustments in tactics and policy.

“We’re at a point where we have to decide what we’re up to there,” said Milton Bearden, a former CIA station chief in Pakistan who was deeply involved in the Afghan resistance to the Soviet invasion in the 1980s. “This is the time to sit down, take off the rucksack, and assess where you are.” Among other things, he said the Bush administration should stop bombing Afghanistan, as it did earlier last week in Oruzgan province.

U.S. officials were reminded of the difficulties they face in recent days when it appeared that Uzbek and Tajik factions from its old allies in the northern alliance were about to fight in the northern city of Mazar-e Sharif. That near-breakdown into localized civil war was averted only after determined intervention by the CIA, Special Forces officers, and the Karzai government, officials said.

Some military experts predicted this new, more political phase of the war could prove even more troublesome than last winter’s bombing of the Taliban front lines and the pushing of al-Qaida out of the country.

“I am fairly pessimistic,” said Andrew Krepinevich Jr., a defense strategist at the independent Center for Strategic and Budgetary Assessments and a frequent Pentagon consultant. “We won Phase One of the war, but Phase Two, supporting the successor regime, is the kind of military operation that is more difficult.”

Words of warning

To be sure, the majority view among U.S. officials and military experts is that U.S. policy there is still on track. But the strong minority view is that the United States could face real trouble in Afghanistan, especially if it fails to adapt its tactics as conditions change.

“We may be sliding into a losing dynamic,” said retired Navy Capt. Larry Seaquist, an expert in security strategy. “There is not much positive data in view.”

As evidence of a drift in the U.S. approach in Afghanistan, he and others pointed to the incident last week in which more than 100 Afghan civilians were, according to Afghan accounts, injured or killed by a U.S. airstrike aimed at suspected Taliban hideouts. “Our forces seem to be chasing hither and yon and stumbling into one friendly-fire mess after another,” he said.

Ethnic, Pakistan dilemmas

Pessimists such as Seaquist worry about three trends they see, all related to the Pashtuns, Afghanistan’s predominant ethnic group. Together, they fear, these trends could snowball into surprising trouble for the United States and for its allies in the Afghan and Pakistani governments.

The first is the resentment engendered by the months-long hunt in southern Afghanistan for Mohammed Omar and other Taliban leaders. To some defense experts, the Oruzgan “friendly-fire” incident underscored the diminishing returns of this effort. “We are now doing things that appear to give marginal return but at a potentially very high cost,” said John Warden, a retired Air Force strategist.

Others worry that the hunt for Taliban leaders continues only because of a strategic drift. “We are running the risk of letting our participation degenerate into continuous tactical scrapes without decisive action,” warned retired Army Col. Robert Killebrew.

The second trend is the Pashtun suspicion that the United States still backs the Tajik and Uzbek commanders who formed the core of the northern alliance, to the detriment of Pashtun ambitions to play a larger role in the new government.

“There are extraordinary levels of discontent among the Pashtuns,” said Robert Templer, Asia program director for the International Crisis Group, a conflict prevention organization.

Opening a new front

The third Pashtun-related trend is the recent expansion of the war into Pakistan, now arguably a more important front than the war in Afghanistan. Tribesmen along both sides of the border mainly are ethnic Pashtuns. There the war is even harder to follow than it is in Afghanistan, with neither the United States nor the Pakistani government disclosing much about operations.

If Pakistan’s recent crackdown on al-Qaida falters, then the entire U.S. effort in the region could crumble, experts warned. But how to bolster the Pakistani effort remains controversial.

Few doubt that the destabilization of Pakistan would represent a major defeat for the United States in the war. “If Pakistan falls apart, our ability to pursue al-Qaida in the region falls apart with it,” emphasized former U.S. diplomat E. Wayne Merry.

To avoid that, Deputy Secretary of State Richard Armitage recently told Congress it would be necessary to prevail against al-Qaida in Afghanistan and Pakistan. “I don’t think we’re actually going to have a success unless we’re successful in both countries,” he said.