Many in the media have wondered aloud why General David Petraeus would have agreed to a "demotion" in moving from the Commander of the US Central Command to what is in effect, a subordinate effort in Afghanistan. Here are three reasons all of which are or could be in play:
1. The military calls them "orders" for a reason. If this is what the Commander in Chief wanted, then the military mind is hard wired to gulp down and get it done. Yes of course, Petraeus could have declined the command--but that just isn't the way it is done. You do the hard things your boss asks you to do so that you get to go on and do more hard things.
2. The challenge. Petraeus strikes me as a guy who thrives on challenge. I imagine that while he's come to enjoy the emoluments associated with being a combatant commander, riding to the sound of the guns is another hard-wired instinct in many a military mind--and Afghanistan is where the shooting is.
3. The deal. I'm sorry--but this is a conservative political website, and we live in a cynical age. Every person I've ever talked to in the Army who knew David Petraeus at any level refers to him as "ambitious". I consider this to be a positive trait--though others may not. I have a feeling that the Administration gave Petraeus the sense that if he went and did this job for the President, he would be the next Chairman of the Joint Chiefs of Staff. ADM Mullen has about 18 months left in the job, and the beauty contest to replace him has already begun. Make no mistake (think of Mr. Obama when you read that), Petraeus would have been a favorite even without this latest post--but I can easily see the wheeler-dealers in the West Wing making the pot right by clarifying the competition from the outset.
Finally, command of the field army in Afghanistan is surely NOT a demotion. It is the most important foreign engagement underway, it is a centerpiece of Administration strategery, and now the President is "all in". Whatever "lack of interest" McChyrstal felt is unlikely to continue, and I imagine Petraeus is going to get his weekly one on one with the One as a matter of course.