WASHINGTON – U.S. Defense Secretary Robert Gates on Monday replaced the top U.S. and NATO commander in Afghanistan and picked a former special forces commander to oversee President Barack Obama's military strategy against a growing Taliban insurgency.

Gates said he asked for the resignation of Army General David McKiernan less than a year into a command that normally would last 18 to 24 months after concluding the new U.S. strategy in Afghanistan required fresh military thinking.

He recommended Obama name Army Lieutenant General Stanley McChrystal, a former Green Beret, to take over command of the 45,000 U.S. troops and 32,000 other forces from other NATO countries now in Afghanistan.

McChrystal, currently the director of the U.S. military's Joint Staff, must be nominated by Obama and confirmed by the U.S. Senate before he can take up the post.

Gates also named Lieutenant General David Rodriguez as deputy commander of U.S. forces in Afghanistan. Rodriguez was lauded by Pentagon officials for a counterinsurgency effort he led in eastern Afghanistan while commander of the Army's 82nd Airborne Division.

This is the right time to make the change, Gates told reporters at the Pentagon days after returning from his latest trip to Afghanistan.

The way I look at this is as McChrystal and Rodriguez as a team. They each bring tremendous skills in a variety of areas that are very pertinent to the kind of fight that we have (in) Afghanistan. And it is their combined skill set that I think gives us some fresh opportunities looking forward.

U.S. forces have been in Afghanistan since a 2001 invasion that toppled its Taliban leaders who had harbored the al Qaeda network responsible for the September 11 attacks on the United States.

Lately violence in Afghanistan has surged to the highest levels seen since the initial invasion.

ELEVEN MONTHS ON THE JOB

McKiernan, who became NATO commander in Afghanistan last June and added the top U.S. command last fall, is the chief architect of the current force build-up that is expected to more than double the number of U.S. troops in Afghanistan to 68,000 by the end of the year. There were about 32,000 troops there at the end of December.

Many of the extra forces will be deployed in southern Afghanistan where officials say the Taliban has made inroads because of a lack of western forces.

McKiernan has pushed for an additional 10,000 troops in 2010, a proposal that appeared to run afoul of Gates who has expressed a reluctance to boost the force level beyond 68,000 troops.

Gates acknowledged that McKiernan's departure from Afghanistan likely would mark the end of his military career.

General McKiernan was fired in a very public manner, said military analyst Andrew Exum of the Center for a New American Security, a Washington think tank.

Policymakers for a while had been losing faith in General McKiernan's ability to really understand this conflict, he said, describing a shift from McKiernan's terrain- and enemy-focused strategy to a population-centered battle plan.

The new Obama plan for Afghanistan calls for a military push to reverse deteriorating security, a surge of civilian aid and development assistance, and possible reconciliation between the Kabul government and some members of the Taliban.

The reshuffle represented a shift in focus right now to a different command style at a very critical period in the war, said analyst Anthony Cordesman of the Center for Strategic and International Studies, a Washington think tank.

But in pursuing a clear, hold, build strategy to pacify Afghanistan, the new commanders face daunting problems, ranging from insufficient civilian development experts, inadequate local Afghan forces, a dysfunctional international aid system and the self-imposed caveats that limit some NATO allies' ability to fight, Cordesman said.

A week ago, Afghan President Hamid Karzai met Obama in the White House with the two countries at odds over civilian casualties from U.S. air strikes in Farah province. Karzai called on Washington to halt air strikes in his country only to be rebuffed by U.S. officials.

Washington has also denied charges that it used burning phosphorus in the latest attacks on two villages in Farah province where Karzai put the death toll at 130 people.

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