The move comes as the White House begins an intense debate this week over the way ahead for Afghanistan and whether more troops are needed there. The faster redeployment from Iraq could make it easier to send more forces to Afghanistan.
Gen. Ray Odierno, the top commander in Iraq, said Wednesday he will speed the drawdown of American troops by sending home about 4,000 next month, leaving about 120,000 there for the January elections. By next summer, there should be only about 50,000 US troops there.
"That's a bit faster than we originally planned," General Odierno told a House panel on Capitol Hill Wednesday.
The security environment is dictating the faster drawdown. Roadside bomb attacks and other violence continue to fall and are now on par with the summer of 2003, when security in the post-invasion environment was considered relatively good.
The speedier withdrawal comes in part by reducing the number of combat brigades in the western province of Anbar from two to one. Anbar was the seat of the violent Sunni insurgency beginning in 2004 and is now relatively peaceful.
It's not clear that the faster withdrawal from Iraq is connected to the debate over troop levels in Afghanistan. But having more troops at home could make a decision to send more forces to Afghanistan that much more politically palatable.
The military, meanwhile, is confronting a challenge as it draws down in Iraq and maintains or increases its engagement of troops in Afghanistan. At the same time, it is trying to increase "dwell time" – the period troops spend at home between deployments.
Pentagon officials describe the various demands in terms of boxes: They have to have enough in each of the Afghanistan, Iraq, and dwell time boxes to succeed at each mission and maintain the health of the force.
Soldiers currently have at least 12 months of dwell time before having to deploy again for 12 months. By 2011, Army leaders hope to have soldiers home for 24 months before deploying to a war zone for 12 months. The Marine Corps, which generally deploys for seven months at a time, leaves most marines at home for about 14 months between deployments.
With improved security in Iraq – and pressure to show progress and bring troops home – the drawdown is beginning to take form. The American military has also sent home about 150,000 pieces of equipment, Odierno said. Odierno said he is "confident" of the security environment while noting that the January elections still pose a concern.
But he said that within two months after the Iraq election he would have a good idea of whether continued drawdown is advisable.
"We can speed up or slow down," Odierno said.
Ultimately, all combat troops are to be out of Iraq by August 2010 and all American forces removed from the country by December 2011. It is likely that some American troops will stay in an advisory role for years to come, but that would come under separate agreement.
Some military officials and conservatives outside the Pentagon worry the drawdown will occur too quickly. Specifically, some would like to see at least 50,000 troops remain in Iraq after all combat forces leave by August 2010 and stay there until the end of 2011.
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