Abuse of prisoners happened - but it wasn't part of a pattern.
The Red Cross complained about it - but top US commanders didn't always see those reports.
Military intelligence was in charge of Abu Ghraib prison - but only for the purpose of defending it.
Those are among the key assertions of US military leaders. In Washington they are attempting the difficult task of limiting damage from a prison scandal that gets more complicated by the day - while at the same time convincing the US public and world at large that justice is being done.
"This is a huge policy challenge to the military leadership," says a retired high-ranking officer who requested anonymity.
At a Senate Armed Services Committee hearing on Wednesday the top commanders of troops in Iraq discussed the chain of responsibility for prison abuses in more detail than has previously been made public.
Gen. John Abizaid, head of US Central Command, told senators that systemic problems did contribute to the events at Abu Ghraib. In other words, the abuses can't all be blamed on a few rogue soldiers acting in the dead of night.
Further investigations are now underway, General Abizaid noted.
"We will follow the trail of evidence wherever it leads," he said.
On the other hand a probe launched in February by the Army's inspector general, Lt. Gen. Paul Mikolashek, found no pattern of abuse of prisoners held in Iraq and Afghanistan, said Abizaid. Instead, it found problems in training and organization for detention operations.
"There was also, clearly, criminal misconduct that took place, and that criminal misconduct is not the subject of any order or policy that I believe exists anywhere," said Abizaid.
At the same time, Abizaid and his fellow panel members struggled with an issue that has become hot in Washington in recent days: Red Cross reports complaining about prison conditions that were forwarded to US military commanders last year.
Senior US officials saw a Red Cross report detailing abuses at Abu Ghraib as early as last November, but didn't launch an investigation for months, according to published reports. Reportedly some officials went so far as to try to curtail Red Cross access to prisons after seeing the group's complaints.
Such reports move erratically through the US chain of command, the generals admitted to the Senate. Abizaid said that he did not see a negative report from February of this year until this month.
"We have a real problem with [Red Cross] reports and the way that they're handled . . . I'll just said that we don't all see them," said Abizaid.
The generals admitted that the chain of command at Abu Ghraib had become tangled, with military intelligence officers in charge of some functions, and military police in charge of others.
But that was done not to increase the flow of intelligence, but for the base's own protection, said Lt. Gen. Ricardo Sanchez, commander of the multinational forces in Iraq.
The base had been receiving a large amount of fire from insurgents, said General Sanchez.
"I issued a fragmentary order that placed all elements at Abu Ghraib under the tactical control of [military intelligence]," said Gen. Sanchez. "The specific order states that this was for forward operating base protection and for security of detainees."
On another chain of command issue, Sanchez said he had never seen a document called "interrogation rules of engagement" until shown it at a previous Senate hearing.
"I had no role in preparing it or approving it," he said.
In general, the military commanders seemed to be trying to contain the effects of the scandal, say some experts.
"It looks to me like they're trying to build a firebreak as low as possible to keep this from spreading up the chain of command," says Pat Lang, former head of Middle East intelligence at the Defense Intelligence Agency.
Assigning responsibility for such misdeeds by underlings is a difficult issue for the chain of command, note other experts.
Commanders are supposed to be responsible for everything troops under them do. Yet the military hierarchy is not one of unquestioning obedience and clear orders.
James Jay Carafano, a retired Army officer who is now a security expert at the Heritage Foundation, says that it's possible that someone at some point said something along the lines of "you know what I want done. I don't want to hear how you do it."
That could be a prescription for abuse, he says.
But at the same time. soldiers are taught that they are not supposed to follow illegal orders. Asked to "take care" of a prisoner, a soldier is within his rights to ask whether he is being expected to break the rules of the Geneva Convention.
The commander "will say 'of course not,' " says Carafano. "That's all it takes."
Conversely, even if Abu Ghraib guards contained some abusers, things went on too long for responsibility to be contained.
"This doesn't happen if you don't have some command failure," says Carafano.