Why do I feel like I've seen this movie before? I'm hoping against hope for a different ending this time: America having the strength to walk away from something that will drain our resources with no clear goals in sight.

The top U.S. and NATO commander in Afghanistan warns in an urgent, confidential assessment of the war that he needs more forces within the next year and bluntly states that without them, the eight-year conflict "will likely result in failure," according to a copy of the 66-page document obtained by The Washington Post.

Gen. Stanley A. McChrystal says emphatically: "Failure to gain the initiative and reverse insurgent momentum in the near-term (next 12 months) -- while Afghan security capacity matures -- risks an outcome where defeating the insurgency is no longer possible."

His assessment was sent to Defense Secretary Robert M. Gates on Aug. 30 and is now being reviewed by President Obama and his national security team.

McChrystal concludes the document's five-page Commander's Summary on a note of muted optimism: "While the situation is serious, success is still achievable."

But he repeatedly warns that without more forces and the rapid implementation of a genuine counterinsurgency strategy, defeat is likely. McChrystal describes an Afghan government riddled with corruption and an international force undermined by tactics that alienate civilians.

But Obama is trying to figure out whether that's actually the road he wants to take:

Instead of debating whether to give McChrystal, the top U.S. commander in Afghanistan, more troops, the discussion in the White House is now focused on whether, after eight years of war, the United States should vastly expand counterinsurgency efforts along the lines he has proposed -- which involve an intensive program to improve security and governance in key population centers -- or whether it should begin shifting its approach away from such initiatives and simply target leaders of terrorist groups who try to return to Afghanistan.

McChrystal's assessment, in the view of two senior administration officials, is just "one input" in the White House's decision-making process. The president, another senior administration official said, "has embarked on a very, very serious review of all options." The officials spoke on the condition of anonymity to discuss internal White House deliberations.

Obama, appearing on several Sunday-morning television news shows, left little doubt that key assumptions in the earlier White House strategy are now on the table. "The first question is: Are we doing the right thing?" the president said on CNN. "Are we pursuing the right strategy?"

"Until I'm satisfied that we've got the right strategy, I'm not going to be sending some young man or woman over there -- beyond what we already have," Obama said on NBC's "Meet the Press." If an expanded counterinsurgency strategy in Afghanistan contributes to the goal of defeating al-Qaeda, "then we'll move forward," he said. "But, if it doesn't, then I'm not interested in just being in Afghanistan for the sake of being in Afghanistan or saving face or . . . sending a message that America is here for the duration."