"To be completely blunt with you, it probably makes it more palatable but that's not the purpose," Biden told "Early Show" co-anchor Harry Smith Wednesday. "The purpose is to make it clear to [President Hamid] Karzai and his government, that up until now has been unwilling to step up to the ball, 'Fellas, you've got to step up to the ball.'"
Mr. Obama announced plans Tuesday to at the fastest pace possible, with the first deployment of new Marines likely coming by Christmas. The president vowed to begin drawing down forces by July 2011.
Biden said it was a "date certain to begin the process" because he's confident that the revamped U.S. strategy will effectively stabilize the region. But the timetable for withdrawal drew immediate criticism.
"If you tell the enemy when you're leaving, it despirits your friends because they have to stay there in the neighborhood," Sen. John McCain, R-Ariz., told Smith, though he supports the president's overall strategy.
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Biden said the president's plan will bolster both the Afghan and Pakistani governments in their struggle against Taliban and al Qaeda militants.
"All along I've been arguing the strategy is more important than the numbers. And the president laid out the strategy. This is a regional issue. Number one priority [is] al Qaeda; number two [is] Pakistan; number three [is] giving the Karzai government a fighting chance to be able to sustain itself. The threat to the United States remains in the mountains in Pakistan. That's where we have to keep our focus."
The restive border region between the two nations has become a safe haven for militants and is widely believed to house al Qaeda leadership, including Osama bin Laden.
Biden said the president's plan will offer economic assistance to Pakistan and involves closer work with that country's military on counterterrorism. Pakistan is currently engaged in its largest military offensive against militants in the mountainous northwest region but has also seen a drastic increase in terrorist attacks on civilians and government targets.
Despite the criticism from McCain, the president's plan may face its toughest resistance from fellow Democrats and liberals, who have grown increasingly restless over the eight-year conflict.
Biden said the refined strategy should assuage the skeptics.
"We have narrowed the objective. We know exactly what our interests are for the United States. …We're going to be a lot safer, a lot more secure. And we will, in fact, be able to leave Afghanistan eventually with a government that's able to take care of itself."