Even as critics decry US policy there, General Petraeus is widely credited for implementing a more pointed strategy that, along with the surge of 30,000 American troops, has led to reduced violence on the ground.
But the move to reassign him to Central Command may help emphasize the NATO-led mission in Afghanistan, which members of Congress, analysts, and military officials believe is suffering from a lack of focus. General Petraeus has earned a reputation as an expert in fighting insurgencies, and that expertise is much needed in Afghanistan, analysts say.
General Odierno recently finished a tour as Petraeus's deputy there, which means he could take over with little disruption, Mr. Gates told reporters Wednesday. "General Odierno is known recently to the Iraqi leadership, he's known to the Iraqi generals, and he is known to our own people," Gates said. "He has current experience and so the likelihood of him being able to pick up – for this baton-passing to be smooth – is better, and the odds are better with him than with anybody else I could identify."
Petraeus will now have to broaden his view considerably, with Iran, Pakistan, and Afghanistan added to Iraq as his primary focus. Or as Michael O'Hanlon, a senior fellow with the Brookings Institution, a think tank in Washington says, "He was focused on one big problem, now he has four."
Petraeus has focused on not squandering successes over the last year and accordingly has not been seen as pushing aggressively toward withdrawing more troops from Iraq. But as head of Central Command, he will have to juggle concerns about the health of the force as well as maintain the security situation, not only in Iraq but also in Afghanistan, says Mr. O'Hanlon, who viewed both nominations as positive.
"There may be some concern that [Petraeus] is not committed to Afghanistan, but he's a can-do guy who doesn't like to fail."
Gates acknowledged that he was installing new commanders in key positions prior to a new administration in the White House, but he said he did so out of the need for continuity. The next president is free to make changes if he or she desires, he said.
The command changes, which require Senate approval but are likely to occur in the coming weeks, mean Petraeus probably won't leave Baghdad until late summer or early fall, Gates said.
Petraeus himself is still expected to make an assessment of the security situation in Iraq by fall – 45 days after the last surge brigade has left Iraq in July – to determine if an additional brigade could return home without being replaced.
The nomination of Petraeus to the Central Command post, which was vacated last month when Adm. William "Fox" Fallon abruptly resigned, was not unexpected. It was originally thought Petraeus would become the commander of US European Command and the Supreme Allied Commander of NATO troops in Brussels. But after Admiral Fallon resigned, over his increasingly public views on Iran that appeared to be at odds with the White House, speculation centered on Petraeus to replace him.
The decision to send Petraeus to Central Command and Odierno back to Baghdad hints that there is a shallow bench of officers suited for the job in Iraq. Gates acknowledged that there are only a "handful of generals" who have the experience necessary, but also said the vacancy left by Fallon's resignation left him few options. "So I'm faced with a critical combatant command where a commander is needed and a commander who knows what's going on in the region," he said.
Odierno was seen as a tough and sometimes overly aggressive commander during the invasion of Iraq in 2003 and its aftermath. At the time, US Marines who handed over the command of the northern Sunni city of Tikrit to Odierno and his 4th Infantry Division complained of his "very aggressive" approach toward Iraqi civilians, and other officials thought he was indiscriminate in his "sweeps" of Iraqis that led to a swelling population at Abu Ghraib prison.
Since then, however, many believe he "got the memo," and has softened his touch. As Petraeus's deputy, Odierno was the day-to-day commander and implemented his boss's counterinsurgency strategy – protecting the local population while capturing or killing individuals fomenting violence against central, provincial, and local governments.
One military source requesting anonymity describes Petraeus as the "strategic thinker" and Odierno as the "tough operations guy."
Some believe that relationship has prepared Odierno well to become the chief strategist there.
Some observers in Baghdad say they will be watching how Odierno adapts to postsurge Iraq, where US forces are to drop down to about 140,000 – and gradually assuming more of an oversight role with Iraqi security forces by the time he arrives as early as late summer.
"Our ground forces' readiness and battles in Afghanistan and against al-Qaida in Pakistan have suffered as a result of the current costly Iraq strategy," Reid said in a statement. "These challenges will require fresh, independent, and creative thinking and, if directed by a new president, a commitment to implementing major changes in strategy."
Odierno had already been nominated to become vice chief of the Army. That nomination will be withdrawn and Lt. Gen. Peter Chiarelli will be nominated in his place. General Chiarelli, who had been on the short list to replace Petraeus in Iraq, has been Gates's senior military aide for more than a year.