The nation's top military man, Marine Gen. Peter Pace, said American troops in Iraq have a duty to intercede and stop abuse of prisoners by Iraqi security personnel.
When Defense Secretary Donald H. Rumsfeld contradicted Pace, the general stood firm.
Rumsfeld told the general he believed Pace meant to say the U.S. soldiers had to report the abuse, not stop it.
Pace stuck to his original statement.
"If they are physically present when inhumane treatment is taking place, sir, they have an obligation to try to stop it," Pace told his civilian boss.
The unusual exchange occurred during a discussion at a news conference about the relationship between U.S. forces in Iraq and an Iraqi government considered sovereign by the United States.
A questioner asked whether the United States and its allies might be deemed responsible for preventing mistreatment of people under arrest in Iraq, given that the U.S. and its allies train Iraqi forces.
"There are a lot of people involved in this, dozens of countries trying to help train these Iraqi forces. Any instance of inhumane behavior is obviously worrisome and harmful to them when that occurs," Rumsfeld said. "Iraq knows, of certain knowledge, that they need the support of the international community. And a good way to lose it is to make a practice of something that is inconsistent with the values of the international community."
He added: "Now, you know, I can't go any further in talking about it. Obviously, the United States does not have a responsibility when a sovereign country engages in something that they disapprove of."
Pace, chairman of the Joint Chiefs of Staff, was asked what orders the troops have to handle such incidents. He responded: "It is absolutely the responsibility of every U.S. service member if they see inhumane treatment being conducted, to intervene, to stop it."
He said soldiers who hear of but don't see an incident should deal with it through superiors of the offending Iraqis.
That's when Rumsfeld stepped to the microphone and said, "I don't think you mean they have an obligation to physically stop it. It's to report it."
Pace then repeated to Rumsfeld that intervening when witnessing abuse is the order the troops must follow, not just reporting it.