"...(is) Obama's move to the middle is simply a political gambit aimed at appealing to the crucial independent and moderate voters or whether it is the sign of a nuanced candidate seeking to avoid taking rigid positions on difficult and changeable issues?"My answer?
This is less a matter of political expediency than it is about an illustration of readiness for the office of President.
Someone who is ready for the Presidency would make known from the beginning that he would consider the advice of his military advisors before making any decisions on pulling out.
The problem here isn't the current obvious political expediency, it is Obama's willingness to play politics with the lives of our soldiers. His original and continued promise(that can't be understated) to pull out within 16 months flies in the face of any statement that exhibits willingness to listen to military leadership.
His shift now is a necessary one if he becomes President, but it is not one he should have needed to make in the first place.
Do you really want to elect the last kid in class that figured out the math problem?