Lt. Gen. James N. Mattis, who brought the criminal charges in the Haditha case, has shown no reluctance to take hard-nosed actions against Marines.
Mattis, commander of the Marine Corps Forces Central Command, in 2003 initiated an investigation of the treatment of Iraqi prisoners by Marines. The investigation, which came before the Abu Ghraib prison scandal, led to the court-martial convictions of a sergeant and a major in the death of a prisoner and to a revision of Marine procedures for handling prisoners.
He also ordered the investigation that led to murder charges against Lt. Ilario G. Pantano in the 2004 killings of two Iraqis, probably the most high-profile case of alleged misconduct by Marines until the November 2005 deaths of 24 Iraqis in the town of Haditha. Pantano was acquitted.
But Mattis' handling of a case involving the town of Hamandiya, in which seven Marines and a Navy corpsman were charged with dragging an Iraqi from his home in April and killing him, suggests that he is willing to show leniency for junior enlisted Marines who admit wrongdoing. In an e-mail to The Times this week, he referred to the "morally bruising conditions of Iraq" where it is often difficult to distinguish friend from foe.
The Hamandiya case also suggests that he may be less willing to be lenient with more senior enlisted personnel for not showing leadership. All eight defendants in Hamandiya were charged with capital murder, which could have brought the death penalty.
Mattis allowed four of the eight to plead guilty to reduced charges and receive sentences of 12 to 21 months in the brig. He vetoed the military judge's recommendation that the four be given dishonorable discharges.
The four defendants with greater seniority and allegedly more culpability in the killing are to stand trial next year.
As a combatant, Mattis, nicknamed "Mad Dog" by his troops, prefers speed and a relentless attack style. His straightforward and often salty rhetoric is tailor-made for infantry troops.
But such rhetoric belies a man who is deeply read in history and military tactics and who, after the fall of Baghdad, pushed for the military to adopt a conciliatory attitude toward the Iraqi populace.
He was a battalion commander during the Persian Gulf War in 1991 and, as a general, led Marines into Afghanistan in 2001. In 2003, as commander of the 1st Marine Division, he led troops into Iraq.
To each Marine and sailor he provided a one-page order telling them to destroy Iraqi forces but to show compassion for civilians and prisoners: "Engage your brain before you engage your weapon."
In April 2004 he was at the forefront of the fight against the insurgent stronghold of Fallouja.
Later he was assigned to head the Marine Corps Combat Development Command at Quantico, Va., and was one of the coauthors of the military's recently issued counterinsurgency manual.
He returned to Camp Pendleton this year in his current role as commanding general. He has made repeated visits to troops serving in Iraq.
Because of his combat experience and expertise in counterinsurgency, Mattis is rumored to be a possible candidate for a high-level command in Iraq under new Defense Secretary Robert M. Gates.
In a recent trip to Marine outposts in the expansive Al Anbar province, Mattis talked to Marines about training the Iraqi army and winning support from civilians. But he also mentioned the insurgent threat in the province.
"This is not sectarian violence," he told them. "This is Al Qaeda in Iraq. We expect you to kill them."