"Obviously, at some point, the surge has to end," Petraeus said in an interview Thursday with National Public Radio, acknowledging that the buildup would become nearly impossible to maintain by the middle of 2008. "We're keenly aware of the strain that has been placed on the services," he added.
Marine Gen. Peter Pace, the outgoing chairman of the Joint Chiefs of Staff, said this week that no new Army troop extensions would take place, meaning April is likely to be the longest the buildup could be sustained.
The White House may not be completely out of the political woods for now. House Democrats have indicated they may revisit the war debate before they start their August recess, and Congress could come back early from its break next month for an Iraq-related vote, although that appears unlikely.
The most important vote will come from Bush himself, who on Friday gave no indication that he was inclined to call off the current offensive. In a brief Rose Garden appearance after a meeting with veterans' and military support organizations, Bush called on Congress to give the military more time, insisting the surge was showing progress.
"These successes demonstrate the gains our troops are making in Iraq, and the importance of giving our military the time they need to give their new strategy a chance to work," Bush said.
Just how long that might take was brought into stark relief by Gaskin, the Marine general in charge of U.S. forces in Al Anbar province. Stability in Al Anbar, repeatedly cited by Bush as a success story, will require U.S. troops to remain until Iraqi forces can take over, Gaskin said.
"I believe it's another couple of years in order to get them to do that -- and that's not a political answer, that's a military answer, and what it takes to train the young men and get the leadership that they need to be able to do what an army does," Gaskin said.
Times staff writers Paul Richter, Doyle McManus and Noam N. Levey in Washington contributed to this report.