COMBAT OUTPOST ZEROK, Afghanistan >> Nestled amid the pine-studded mountains in eastern Afghanistan, this small base a dozen miles from the Pakistan border was once one of the most dangerous places in Afghanistan. Insurgents nearly overran it in 2009. Last year mortars rained down on the base nearly every other day.

But security has vastly improved here. The outpost, in the northeastern mountains of Paktika province, has not been shelled since late last summer, due largely, soldiers here believe, to a shift in tactics that started when a new unit came in and began relentlessly patrolling the surrounding mountains, always on foot and usually at night. The incessant patrols took away the insurgents’ vantage points, and they have barely engaged since.

Now the unit, Company E of the 2nd Battalion, 506th Infantry Regiment — a part of the 101st Airborne Division — is trying to solidify those gains by pushing the Taliban out of several nearby villages that U.S. commanders believe are among the last of their sanctuaries in the area before the warmer summer months, when insurgent activity is heaviest.

“The goal is to make them fight back in, and we’ve taken that to heart,” said Capt. Henry Hansen, the company’s commander. “Come the May time frame, we may get some of those foreign fighters who haven’t been tracking what we’ve been doing here, but we’ll be ready for them.”

Military officials cannot say whether the company has simply pushed the insurgents into hiding or driven them elsewhere. And everyone expects to see an uptick in fighting this summer.

But for now, the improved security is fostering other benefits. More and more elders from surrounding villages trek miles across rugged terrain to attend weekly shuras, or meetings, held at an Afghan police compound attached to the base. Last week, a recalcitrant tribe agreed to come to the compound to sit down with a rival tribe over a timber dispute, allowing the Afghan army to mediate.

In a province where such issues are often resolved through conflict or through the Taliban’s shadow justice system, the meeting was a victory, a show of faith in the coalition — and by extension the Afghan government.

“It’s the inkblot theory,” Hansen said. “You focus on one area and it spreads out.”

The company was part of the last “surge” brigade to arrive in the country, part of the U.S.-led initiative to tamp down the insurgency and begin laying the foundation to transfer security responsibilities to the Afghan security forces by the end of 2014. Last year, a single battalion was responsible for securing the entire province. Now the same area is covered by nearly a full brigade, about six times the combat power.

The province of perhaps a half million people is seen as a strategic crossing ground for insurgents entering the country from militant safe havens in North and South Waziristan in Pakistan. The base, an ungainly collection of dirt barriers, guard towers and plywood command posts, serves as a launching pad for securing villages and cutting off well-worn Taliban paths in the province’s northeastern mountains.

While U.S.-led forces have struggled in other isolated mountain valleys — abandoning the Korengal and Pech Valleys in the northeastern province of Kunar — the turnaround here in this rugged part of the country has been remarkable.

Company E arrived in August amid nearly daily attacks. Nearly half the soldiers in the company it replaced received Purple Hearts. A “60 Minutes” television crew visiting that summer captured footage of the base under mortar attack and then came under fire itself as it accompanied an armored vehicle convoy to a nearby village.

Collected bits of jagged steel and mortar tails fill a “shrapnel garden” in the center of the compound, a testament to past attacks. But since arriving, Company E has added little to it.

Early on, the company’s patrols came under sporadic gunfire. “If we sat in one place 24 hours, the enemy attacked,” said 1st Sgt. Steve Chandler Jr., 40. But the patrols — 211 in the first 150 days — were having their intended effect. Intelligence intercepts showed an enemy confused about how many U.S. troops were scouring the hills.

Sgt. Anthony Stegmeier, 27, of Indianapolis, is one of the few Company E members who was with the unit when it was stationed at this same outpost from March 2008 to March 2009.

“The patrolling wasn’t as strenuous as it is now, and we took a lot more IDF, sometimes daily, sometimes every other day,” he said, referring to indirect fire, usually mortars.

With the high ground lost, the militants shifted tactics. They planted improvised explosive devices on ridges. But the patrols seldom took the same path twice and usually avoided easier routes along dry creek beds. Since the unit arrived nearly nine months ago, only two soldiers have been wounded.

“It may be a counterintuitive concept, but the more you patrol, the safer you are,” Hansen said. “If the enemy sees you everywhere, he’s a lot less inclined to attack because he doesn’t know where you are.”

The mountains themselves, some reaching 10,000 feet, have taken their own toll. The company has suffered dozens of sprained ankles, strained backs and other injuries from lugging 90 pounds of gear on the night patrols. One patrol was so long and over such tough terrain the soldiers called it “Bloody Sandals.”

One soldier, Pfc. Kory Russo, 19, of Fort Wayne, Ind., plummeted 30 feet down a ridge during a nighttime mission in October, injuring his back and both knees and marched about two-and-a-half miles back to the base. He was back on patrol three weeks later.

“Everyone was saying it was a miracle I made it,” he said.

Still, nobody is declaring victory. Even as security has improved here, others outposts in the province have come under heavy attacks. In October, Combat Outpost Margah, a few miles closer to the border, repelled a large-scale nighttime assault that left five Americans wounded and 92 insurgents dead.

“I try to be very cautious in talking about the company’s success,” said Hansen, of Hunter, N.Y., “because we could cite success one day and the next day they launch a complex attack.”

The company kept up the patrols through thigh-deep snow in January and February. By April, the missions had become rigorous but mostly quiet affairs, chasing intelligence intercepts that often led to empty hilltops.

Even so, Lt. Jason Eaves, 26, said, it has been better than sitting at the base “and taking rockets every day.”

“Now,” he said, “It’s a lot of chasing ghosts.”

© 2011 The New York Times Company