McChrystal has made it clear that he wants significant progress in the next 12 to 18 months. Assuming the progress he wants is on the security front, it is going to be a real challenge to achieve success without adding significant numbers of troops.
Gates was also asked Monday whether the U.S. is winning the war in Afghanistan. He responded, "I think it's a mixed picture."
Gates said it would be hard to immediately find more troops for Afghanistan, given the more than 100,000 in Iraq that will eventually come home.
"Yes, it would be [hard]....because Stan McCrystal has said he needs things to change in Afghanistan quickly," Gates said.
It could also be hard to convince the public. In a recent ABC News-Washington Post poll, more than half of Americans now call the war "not worth fighting" and support for reducing U.S. troop deployments in Afghanistan is up sharply.
Influential columnist and ABC News contributor George Will is now saying U.S. troops should pull out, and rely on drones, intelligence and air strikes -- an argument sure to be debated in Washington, and one that could divide Capitol Hill.