The US agreement with the Iraqi government calls for all American combat troops to be out of the cities by the end of June next year.
But, according to a report in the New York Times, military planners are now quietly acknowledging that many will stay behind as renamed 'trainers' and 'advisers' in what are effectively combat roles.
In other words, they will still be engaged in combat, just called something else.
"Trainers sometimes do get shot at, and they do sometimes have to shoot back," said John A. Nagl, a retired lieutenant colonel who is one of the authors of the US Army's new counterinsurgency field manual.
US President-elect Barack Obama is facing rapidly approaching, and overlapping, withdrawal deadlines, some set by the Bush administration and the Iraqis, and some set by him.
Apart from the deadline of June 2009, Obama has also set a deadline for the complete withdrawal of American combat forces out of Iraq by May 2010.
Next comes December 2011, the deadline in the status-of-forces agreement to have all American troops out of Iraq.
To try to meet those deadlines without risking Iraq's fragile and relative stability, military planners have said that they would have to reassign some combat troops to training and support of the Iraqis, even though the troops would still be armed and go on combat patrols with their Iraqi counterparts.
So, although their role would be redefined, they would still be in combat mode.
"If you're in combat, it doesn't make any difference whether you're an adviser: you're risking your life," said Andrew Krepinevich, a military expert at the Center for Strategic and Budgetary Assessments, a research group. "The bullets don't have 'adviser' stenciled on some and 'combat unit' on another," he added.
According to Michael E. O'Hanlon, a senior fellow in at the Brookings Institution, roughly 10,000 American troops should remain in Baghdad after next June, with thousands more in other cities around the country.
Currently, there are 146,000 American troops in Iraq, including service and support personnel.