Matt,
I don't think most will say you are out of line - you phrased your question as a question and not as an attack or an indictment.

There certainly is a convergence point for policy and strategy, and the higher in the rank structure regarding a policy and the strategy for realizing it, the closer you are affiliated with it.

The very broad and general policy goal is to see Iraq to a point of stability where it can govern its own affairs, provide for its citizens and participate as a responsible state on the regional and international scene. By doing this we also help to prevent further instability in the region (such as Iran expanding a destabilizing influence & Non-state actors such as AQ or other terrorist organizations expanding into ungoverned spaces) and protect access to the strategic energy resources which are so vital across the world.

Certainly the MNF-I CDR bears some responsibility in meeting those "ends" by helping determine the "means" he'll use to do so. He also bears great responsibility for planning and implementing the "ways". The policy makers - really the administration - must approve the strategy as the tool used to realize the ends. The law makers must approve the appropriation and allocation of the "means" or funding and resources needed to pursue the ways. Congress and the President are of course elected officials - so enter in the people to go with the government and the military - the people get their window through the media.

This was all kind of what Clausewitz theorized in his secondary trinity (the people - the military and its leadership - the government) with regard to considering the nature of war. War makes no sense without its political context else why would you go to war if not for some political reason (usually involving fear, interests or honor).

At the level of war in which GEN Petraeus' operates - policy is part of it. Remember there was a political confirmation process for assigning him to lead MNF-I - politics entered early on. Every General Officer is charged with providing the elected officials their best and most honest military advice to inform policy questions, and although the President is in our Chain of Command - our oath is to preserve the constitution.

Also, I don't think the President has hung him out to dry. Tune in tonight for the President's speech and I think you'll see him take responsibility for the decision to continue the policy.

I hope that helps answer your question. Also for a good read on this pick up any book by Colin Gray.

Best regards, Rob