Mullen has repeatedly expressed frustration that NATO allies have not provided the numbers of troops needed to wage a complex counterinsurgency campaign. He also has expressed concern that the U.S., with continuing heavy commitments in Iraq, does not have enough combat-ready troops to fill the gap. Commanders believe that three brigades, or about 10,000 troops, are necessary.
"Violence is up this year by every single measure we look at," Mullen told members of his staff at a public meeting Monday, noting the spread of roadside bombs known as improvised explosive devices. "The Taliban, by and large, have moved -- not unlike what happened in Iraq -- to the asymmetric, IED-style warfare."
As part of his effort to rethink the Afghanistan mission, Mullen has asked military planners to develop new strategies for deploying additional American troops should they become available.
Last year's troop buildup in Iraq and the overall strain on U.S. ground forces have made it almost impossible to increase force levels in Afghanistan. Many military officials, including top Army leaders, have advocated taking advantage of future troop reductions in Iraq by giving U.S. units more time at home to rest and train.
But in a shift, military planners now have agreed that future troop reductions in Iraq instead will lead to an increase in U.S. units in Afghanistan. The shift followed a lengthy internal battle, a senior Defense official said, speaking of the debate on condition of anonymity.
Still, other officials said that Pentagon planners do not know when they would have additional troops for Afghanistan because the outgoing commander in Iraq, Army Gen. David H. Petraeus, has not ordered further troop reductions.
As a result, officials at the military's Joint Forces Command, the headquarters responsible for identifying units to be deployed overseas, have begun looking to bases in the U.S. for about 1,000 new troops that can be sent to Afghanistan in October to serve as trainers for Afghan government forces.
Gates and the Pentagon's military leadership have identified military trainers as their biggest shortfall in Afghanistan. And the need is growing. A Marine Corps unit sent as a stopgap is due to leave Afghanistan in the fall.
Without significant numbers of new troops available, Mullen's staff has focused on streamlining the international military command structure in Afghanistan. Critics have said that the current multi-branch structure has hampered U.S. and NATO operations by failing to effectively coordinate all military and reconstruction efforts.
