Soldiers of the 1/501st of the 25th Infantry Division begin marching at sunrise just after being air-dropped into a field October 14, 2009 in Paktika Province, Afghanistan. (Photo by Chris Hondros/Getty Images)

More troops will likely be there soon. (Chris Hondros/Getty Images)

By Mark Memmott

"The entire U.S. military" has lined up behind Gen. Stanley McChrystal's request to add approximately 40,000 troops to the international force in Afghanistan, an Obama administration source who is very familiar with policy discussions now underway tells NPR.

"It's historic unity" on the part of the military chiefs, the source adds.

Bruce Auster, NPR's national security editor, tells us that the source says Defense Secretary Robert Gates and Joint Chiefs of Staff Chairman Adm. Mike Mullen are on board with the idea that McChrystal, who commands U.S. and NATO forces in Afghanistan, should get the 40,000 or so additional troops he believes are the minimum number necessary to mount an effective counterinsurgency operation.

There are different ways to do that. One option would be 40,000 more American troops. Another would be to send about 35,000 from the U.S. and another 5,000 or so from NATO partners.

There are at least two other, less likely, options still on the table as Obama and his advisers meet this afternoon to talk over the possibilities. Here are the four choices:

-- "The low option": Adding 10,000 troops, all of them to train Afghan forces.

-- "The hybrid": 15,000 to 20,000 additional troops who would focus on counterterrorism.

-- The mix of 35,000 Americans and about 5,000 from NATO forces.

-- An increase of 40,000; all of them Americans.

And when might a decision be announced? The source says that after the president returns from his 10-day trip to Asia (which begins Thursday), one possible date is Nov. 23, the Monday before Thanksgiving.

NPR's Mary Louise Kelly is scheduled to be on All Things Considered later today with more on this story. Click here to find an NPR station near you.

categories: Afghanistan

1:40 - November 11, 2009