You are correct that it was Bush's timetable as approved by the Iraqi legislature. However, we have 8,000 US contractors armed to the teeth defending our diplomatic facilities, provinicial reconstruction teams, and NGOs. All of this is now under the direction of the State Department. I predict that we will suffer a significant loss of American lives in Iraq under this arrangement. And we could very well see a civil war break out damaging our strategic national interests in the region.
Bush's SOFA with Iraq allowed for non combat troops to stay for longer. They anticipated between 30k and 70k staying.
Obama is responsible for the total abandonment of Iraq.
Campaign Promises on Ending the War in Iraq Now Muted by Reality