Updated at 7:18 a.m. Eastern.
The top U.S. commander in Afghanistan says he's "absolutely supportive" of the 18-month timeline for President Obama's troop surge even if Taliban forces try to wait out the increased U.S. commitment.
Gen. Stanley McChrystal told reporters Wednesday that even if the Taliban lay low, the 18-month period allows time to bolster Afghan military and governing capability to make it harder for the militants to return.
McChrystal also pointed out that the 18-month period to begin a U.S. withdrawal depends on conditions on the ground.
The general spoke after Obamato send 30,000 more U.S. troops to Afghanistan but begin a drawdown in July 2011 as conditions permit.
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Shortly after Obama's speech, Gen. Stanley McChrystal told reporters, "I am absolutely supportive of the timeline," and that the time ahead would be used to build up Afghan forces to convince the people of this war-ravaged country that they can eventually take care of their own security.
"In a counterinsurgency, what we're really trying to do is protect the people," he said. McChrystal added that if the Afghan government used the time to increase its capabilities "then it makes it much more difficult for the insurgents returning."
"But to a degree the insurgents can't afford to leave the battlefield while the government of Afghanistan expands its capacity," he said.
McChrystal said NATO and U.S. forces would hand over responsibility for securing the country to the Afghan security forces "as rapidly as conditions allow" but cautioned that success would also depend on improvements in governance and economic development aid.
He said the coalition must "show clear commitment and resolve" and convince the Taliban "that they cannot win - that there is not a way for the insurgency to win militarily."
"I think the second thing we need to do is to convince them that the reasons that they are participating are not valid," by tackling corruption and improving governance.
McChrystal said he met Wednesday with Afghan President Hamid Karzai for nearly one hour at the presidential palace and described the leader's reaction as "really positive."
"The president was very upbeat, very resolute this morning," he said. "I really believe that everybody's got a focus now that's sharper than it was 24 hours ago."