Another good column on this:
http://pajamasmedia.com/richardfernandez/2010/06/23/last-chance-saloon/#more-9543
A follow-on comment by the author of the column:
"Some wag wrote that the President can spare 10 minutes for Afghanistan, 20 minutes for the oil spill and maybe an hour for the economic crisis. But nothing gets his attention like a threat to his prestige and authority. For that he will meet with aides both day and night. What the McChrystal crisis turned up was that this was one of those things which he was truly scared would get out of hand. This was an ‘ouch’ pressure point.
What follows is pure guesswork and is based on nothing but a hunch. Petraeus was sent in part because of his prestige with the men; one his main tasks is to get all the sneerers and infighters under control. He is there to restore faith and morale and maybe, discipline. Probably Petraeus knew this already but couldn’t act until the top brass got scared enough to take it seriously. I wouldn’t be surprised if there weren’t warning signs all along which we are going to belatedly discover. Now he’s got his hunting license and he’s going.
Lastly, my guess is there is a collision on the ground between the strategic imperatives of Washington empires. Petraeus will go down there and pull one wriggling critter after the other from the drain and exhibit it to his superiors, forcing them to make hard choices among their monstrous progeny, which they won’t make. In other words he will inevitably open a can worms. I can’t think of a better man to do it. The only problem is: where will it go?"