FORWARD OPERATING BASE MASUM GHAR, Afghanistan -- In a natural amphitheatre high among the jagged grey peaks of Afghanistan's Panjwai district, the shock of a village shooting rampage is still settling over U.S. soldiers who served with accused gunman Robert Bales.

The soldiers of Tacoma-based 3/2 Stryker Brigade Combat Team were moving into areas inherited from Alaska-based troops, tracking their armored vehicles to memorize the mazy roads of southern province Kandahar, when more than a dozen people were shot dead in Belandai and Zangabad villages.

Bales' brothers in arms are perplexed and distraught by the March 11 slaughter, which has dragged U.S.-Afghan relations to new nadir, prompting President Hamid Karzai to demand a pullback of NATO forces from Afghan communities.

"We are all talking about Sergeant Bales. I talk with some of the soldiers who served with him and they are all surprised. It saddens the friends of his, because my understanding is it was totally out of character," 3/2 Brigade Chaplain Major Edward Choi told Reuters at the unit's headquarters at Forward Operating Base Masum Ghar.

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The U.S. military last week lodged 17 charges of premeditated murder against Bales, a four-tour veteran, ahead of what is expected to be a long trial. In theory at least, the death penalty is on the table.

Popular leader
Bales had been a popular leader, Choi said, making the massacre even more bewildering. Comrades reject reports his marriage had been in trouble ahead of an Afghan deployment he was reluctant to undertake.

"That is not the case," said Choi, shrugging in frustration. "People that knew him, that dealt with him personally, said he was a great NCO (non-commissioned officer), cared for soldiers, was tactically and operationally professional, loved his wife and kids."

Choi, whose small plywood chapel overlooks a wide river plain and brigade command fenced by concrete blast walls, said some of Bales' comrades had been stressed by moving into a dangerous area that birthed the Taliban, and where its one-eyed leader Mullah Mohammad Omar still has a home.

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Choi said he had no doubt multiple deployments were taking a toll on some of the fighting men. New rules governing elite units like the one Bales was assigned to guard, and wandered from in darkness on the night of the killings, were likely.

"When I speak to some of my leaders, our concern is lack of oversight. There are conventional soldiers attached to special forces who are well trained, off on their own, very mature and growing beards and doing their own thing," he said.

"When you take a 19 or 20-year-old conventional soldier and put him into special operations, they might not be able to handle it."

Captain Janel Schlaudecker, a combat stress counsellor for U.S. soldiers in Panjwai, including Bales' unit, said while there was no explanation for what led to the massacres, she had not noticed an impact on the wider stress levels of Bales' brigade, even among the far-flung infantry units.

"It's so hard to judge how they would respond to this. But they are used to going out there and eating next to nothing, if anything," Schlaudecker said.

"They are used to being under a lot more pressure and not having a lot of sleep. They are wired completely differently. They are lot more resilient."

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Tensions over the incident are still high in Panjwai, an insurgent hotbed west of Kandahar city, and the scene of some of the war's fiercest battles. Scores of Canadian soldiers were killed there before the Americans took over in mid-2011.

U.S. authorities have given the victims' families cash compensation of around $50,000 for each person killed, but at a meeting with district elders this week, U.S. officers and advisers were confronted by angry Afghans demanding to know why more was not done to prevent such an atrocity.

"Local people are very angry. I get hundreds of calls from people who want this soldier tried here, in Afghanistan," said Panjwai radio journalist Abdul Karim, who also runs a curio shop from a shipping container, used by U.S. troops.

Fighting season
Some soldiers worry the massacre will undo hard-won gains over the past year, when insurgent attacks fell 40 percent, and turn sentiment against incoming units of Bales' 3/2 Strykers ahead of the summer fighting months.

The 2012 fighting season is the last which will be fought by NATO in surge-level numbers, as the end-2014 deadline for the exit of most foreign combat troops approaches.

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Insurgents have already carried out small attacks as a bitter winter recedes, but U.S. commanders say this does not mean an emboldened Taliban have brought hostilities forward.

"I think the coming summer will be bad and the new guys are worried," said Staff Sergeant Robert Nelson, 37, a garrulous ex-Marine from Texas who runs the 'Mission One' base shop at Masum Ghar for the outgoing 1/25 Arctic Wolves, now packing to leave.

Colonel Todd Wood, the outgoing U.S. commander for the 25th Infantry Division, said patrols were brushing lightly over Belandai and Zangabad to avoid provoking more anger, but he did not think the massacre would make the fighting months worse.

"Right now it's probably still too early to tell," said Wood, a weathered, hyperactive Iraq veteran from Iowa.

"We've still got villagers that will point out IEDs (improvised explosive devices), we've still got villagers out there that will warn us of a possible attack ... that hasn't changed," he said.

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