New Afghan Mission: Go Hard and Get Out

In his national address Tuesday night, President Obama didn't just outline a new strategy for Afghanistan, he redefined the U.S. mission there, as CBS News national security correspondent David Martin reports.

Gen. Stanley McChyrstal, the to U.S. commander in Afghanistan, told his staff this morning today is the first day of the rest of the war.

"There will be a lot of people who will question whether we can do it," he said. "There are some who will question whether we should do it. But nobody should question from today on whether we will do it."

But "it" does not mean defeating the Taliban. Defense Secretary Robert Gates explained to Congress that the objective is simply to weaken the Taliban and strengthen the Afghans so they can take over the fight.

"The president's new strategic concept aims to reverse the Taliban's momentum and reverse its strength," Gates said.

Here's how the commandant of the Marine Corps, James Conway, explained it to troops fighting in the Taliban heartland of Helmand Province:

"When we can turn this place over to Afghan security forces, army and police, and have a reasonable level of confidence in their government and run their country through whatever devices, we're outta here."

The president's strategy lowers the bar for what U.S. troops must accomplish before they can come home. But it raises the bar for Afghan troops who must start fighting for themselves.

As Gates put it, "We have to build a fire under them frankly to get them to do the kind of recruitment, retention, training and so on for their forces that allow us to make this transition."

July, 2011 marks the second anniversary of the start of major combat operations in Helmand, and more troops are on the way.

"You're going to see about 9,000 additional Marines flow in here pretty quick," Conway said.

If the troop surge isn't producing results by the summer of 2011 it may never work.

"If I came to conclude that we were bogged down and stalemated and we were sending young men and women into a maw with no purpose and no hope of success," Gates said, "I wouldn't sign any more of those orders."

Gates says he hates the term exit strategy but that's what this surge is - a plan to go in hard get out fast.

David Martin

David Martin has been CBS News' national security correspondent, covering the Pentagon and the State Department, since 1993.

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