President Obama is open to trying a new policy in Afghanistan if the proposed surge doesn't work, he said in an interview airing tonight.

The president said that it will likely be clear by December 2010 if the surge is working, and he would be open to a change in strategy.

"I think, by the end of December 2010 whether or not the approach that General McChrystal has discussed in terms of securing population centers is meeting its objectives," he told 60 Minutes. "And if the approach that’s been recommended doesn’t work, then yes, we’re going to be changing approaches."


Obama also emphasized that the July 2011 date outlined in his West Point speech is when the military will "start transitioning into a draw down phase," but is not a hard and fast date for complete withdrawal.

"How many U.S. troops are coming out, how quickly will be determined by conditions on the ground," he said.

"As Commander in Chief, obviously, I reserve the option to do what I think is going to be best for the American people at that point in time."

But the president also nodded to congressional liberals who have expressed skepticism about the troop surge.

He said a date to begin withdrawal sends an important message to Afghans that the U.S. commitment isn't indefinite.

"[I]n the absence of a deadline, the message we are sending to the Afghans is, 'It's business as usual.  This is an open-ended commitment.'" he said. "And very frankly, there are I think elements in Afghanistan who would be perfectly satisfied to make Afghanistan a permanent protectorate of the United States."

Obama said Americans are "familiar with the idea of a surge" due to the war in Iraq.

But conservatives and neoconservative have blasted Obama for announcing the July 2011 timeline, something President Bush did not due when he sent more troops to Iraq.

Obama dismissed those concerns and took a shot at lawmakers and pundits whom he suggested take war too lightly.

"There was a tendency to say, 'We can go in.  We can kick some tail. This is some glorious exercise.'" Obama said. "When in fact, this is a tough business."