Protests have erupted in Afghanistan in outrage at the news of the killing of 16 civilians in the villages of Alkozai and Najeeban in the south of the country.
In the early hours of Sunday morning at least one US soldier murdered them in their beds.
Nine were children. Most were shot in the head. Their bodies were then wrapped in blankets and set alight.
The villages are over three miles apart. Early reports quoted witnesses saying a number of soldiers were involved and that helicopters were flying overhead during the attack.
Afghan guards also report seeing the sergeant accused of the attack taking two trips out of the base that night. He returned from one at 12.30am then left again at 2am.
Agha Lala, a villager, saw more than one soldier when he was awoken by gunfire at about 2am. “I watched them from a wall,” he said.
“Then they opened fire on me. The bullets hit the wall. They were laughing. They did not seem normal. It was like they were drunk.”
He hid, then came out to check on his neighbours. “It was a slaughter. The bullet-riddled bodies were all over the room,” he said. “Is this what the Americans call an assistance force? They are beasts and have no humanity.”
Despite such testimony, US officials insist the slaughter was the work of one officer.
The generals and politicians want to portray the incident as an aberration—as the act of a lone deranged individual.
But such incidents are far from unique (see box). In 2005 US soldiers massacred 24 civilians in Haditha in western Iraq.
The officer under arrest for the latest killings came from Lewis-McChord army base in Washington state. Only last year soldiers from that base were found guilty of organising “kill teams”—gangs of soldiers who kill Afghan civilians for “sport”.
They kept body parts as gruesome souvenirs while trying to cover up their crimes.
The last two months have exposed the reality of what Barack Obama claims is the “exceptional character” of the US military.
In February it was found that copies of the Koran had been burned with rubbish at the US base in Bagram. Thousands protested against the foreign occupation.
In January footage of US soldiers urinating on the corpses of Afghans was discovered.
Such brutality and violence are intrinsic to imperialist war.
Those who train occupying soldiers to be cold-blooded killers want to disown them when they kill the wrong Afghans at the wrong time.
But the occupation of Afghanistan has involved numerous official operations resulting in the deaths of thousands of civilians.
When six British soldiers were killed in a single roadside bomb last week there were renewed calls to end the war. But the people who have suffered the most are the Afghans.
This war was never fought to improve their lives.
Billions have been spent on weapons while children in Afghanistan suffer one of the highest levels of chronic malnutrition in the world.
Everything the Western powers do is for their own strategic interests. They now claim they are staying until 2014 to help train Afghan security forces.
This may change as Obama and David Cameron discuss putting Afghan troops in a “lead” combat role.
This is a familiar tactic in a losing war. They want to leave while avoiding appearing to be defeated. This latest outrage has thrown them into crisis.
Not an isolated incident: the US did the same in Vietnam
On 16 March 1968 soldiers in Charlie company of a US infantry battalion carried out the worst atrocity of the Vietnam war in the village of My Lai.
They murdered 504 civilians in a frenzied attack that lasted for three hours. Soldiers carved “C company” on bodies. Women were raped.
They had been briefed the night before to burn out the village. An officer told them, “Go and get them.”
But afterwards the army establishment attempted a cover-up. One soldier, Colin Glen, wrote to the US commander in Vietnam about the massacre.
He warned that the abuses “are carried on at entire unit levels and thereby acquire the aspect of sanctioned policy”.
Colin Powell, later to become US secretary of state, blocked the complaint.
He wrote, “In direct refutation of Glen’s portrayal is the fact that relations between American soldiers and the Vietnamese people are excellent.”
The public only heard the truth about My Lai when investigative journalist Seymour Hersh exposed the massacre a year later.
My Lai became symbolic of the horror of the US role in Vietnam—and helped turn the tide of public opinion against the war.