Americans share a small observation post with Afghan soldiers in a rugged stretch of Paktika province. U.S. officers are wrestling with separate directives to win key strategic areas and prepare for the impending troop withdrawal. (Kevin Sieff/WASHINGTON POST)

Col. Edward Bohnemann leaned over the rocky bluff at the edge of his brigade’s most remote outpost, staring into a valley near the Pakistan border that is peppered with mud-baked huts and is home to a sea of insurgents.

Bohnemann’s subordinate officers pointed to mountain ridges in the distance, outlining a strategy to vanquish the insurgents by expanding the U.S. presence in the area. But as an incoming commander during the last years of America’s 10-year-old war, Bohnemann wasn’t convinced.

“The question is not, can we build these outposts?” Bohnemann said. “The question is, can they be sustained by Afghan forces?”

When President Obama told Americans in July that the “tide of war is receding” in Afghanistan, 3,100 soldiers from the 172nd brigade were just beginning to arrive in this rugged swath of the country — their first Afghan deployment coinciding almost exactly with the war’s ebb.

The timing leaves Bohnemann to balance two separate directives that are often at odds with each other: to do all he can to defeat insurgents, while also preparing for an American departure by the end of 2014. Last month, during his first visit to the outpost, called Twins, the tension between those priorities played out on the battlefield.

Soldiers in this strategic foothold want to expand upon the work of their predecessors. But many top U.S. officers worry that doing so while the foreign role in the war effort is carefully dismantled might be counterproductive. Americans are already preparing to hand over bases, outposts and checkpoints to Afghans.

Like the rest of Bohnemann’s domain in Afghanistan’s eastern Paktika province, Twins is in a rugged, sparsely populated part of the country, where insurgents come from seven militant networks, crisscrossing the Pakistani border and settling into local villages for weeks or months at a time. The Taliban is a concern, but it’s not public enemy number one.

Bohnemann walked from tent to tent at 10,400 feet, where exhausted U.S. soldiers, who have taken indirect fire every day since they arrived, greeted him.

“I saw these mountains for the first time,” one said, “and my mouth dropped.”

Bohnemann’s men suggested building a series of outposts along nearby ridges, which would provide support to police checkpoints within local villages. Past efforts to establish such checkpoints without mountain outposts have backfired, with insurgents swiftly toppling them.

The larger strategy is to keep insurgents in the east away from what’s often referred to as the “Kabul security zone” — an effort to protect the country’s capital and encourage the central government’s growth. The difficulty of that mission has been underscored over the past two weeks, with an attack last week on the U.S. Embassy and the assassination on Tuesday of former president Burhanuddin Rabbani in his Kabul home.

“Owning the high ground allows us to dominate the terrain and to establish a government presence in the area,” Lt. Col. John V. Meyer told Bohnemann. “We’re going to clean out this entire bowl,” he said, referring to the valley below Twins.

Bohnemann, an affable leader with an easy smile, knew that Meyer’s suggestion would work in the short term, but at this stage of the war, that wasn’t enough to win him over. Although Afghan forces are growing in number and capacity, officials here worry that the United States runs the risk of overbuilding on the eve of its withdrawal, leaving Afghans with bases they cannot man.

“Whatever we do must be Afghan-sustainable,” said Gen. Daniel Allyn, the top U.S. military official in eastern Afghanistan. “If we place an outpost on top of a mountain that’s only accessible by air, we have to make sure they can continue to operate there, given the limitations of their air force.”

Top Afghan commanders are usually candid about their own troops’ limitations in fulfilling a U.S.-designed mission.

“We are a capable force, but without artillery, heavy weaponry and air support, there are many things we cannot do,” said Lt. Col. Mohammad Kazimi, an Afghan battalion commander in Paktika.

The Afghan army’s capacity has increased over the past year, “making my job a lot easier,” Bohnemann said. But other members of the brigade, also known as Task Force Blackhawk, have expressed more skepticism about the ability and loyalty of Afghan soldiers.

Of course, those perceptions could change; they have only recently arrived. Although the U.S. role in Afghanistan is approaching its 11th year, from the perspective of many troops on the ground, the war has just begun. Soldiers inherit this conflict for about 12 months at a time before handing over bases, outposts and intelligence to another crop of servicemen.

Evidence of that recent transition was still visible in Paktika as of last month — signs that still read Task Force Currahee instead of Task Force Blackhawk, soldiers who still got lost on the expansive forward operating base, young infantrymen jumping at the chance to go on their first patrol.

Then there’s the larger question of how a brigade crafts its own mission, makes its own imprint.

Seemingly prosaic dilemmas related to that goal — to build an outpost or not; to expand or cede ground — speak volumes about the state of the war.

“It’s a fine line,” Bohnemann said. “We don’t want to build something today that can’t be used tomorrow.”