Gen. Stanley McChrystal put President Barack Obama in an impossible position. That is why he had to go. A general's tasks involve executing policies made by the commander-in-chief, plotting strategy and winning wars—not playing politics in the media to get at civilian rivals inside the government.

What McChrystal did required Obama to change generals at a decisive moment in the Afghanistan conflict or risk looking weak and out of control. It's not a choice a president should be forced into making. But the McChrystal imbroglio also highlighted the obstacles facing Obama's effort to find a third way between rival policy factions in his own White House.

Everyone on the president's team, including McChrystal, said they had signed off on the Obama compromise: to give McChrystal the troops he said he needed to improve the situation but to place a clear time limit on how long the troops would stay. In practice, the president's advisers continued to feud, sowing uncertainty about what the policy actually was. Those who had been against McChrystal's proposed buildup said Obama's declared deadline of July of next year for beginning troop withdrawals was firm. McChrystal's backers said the deadline was flexible.

The administration was openly divided over how effectively it could work with Afghan President Hamid Karzai. Unlike McChrystal, Ambassador Karl W. Eikenberry and Richard C. Holbrooke, the special representative for Afghanistan and Pakistan, think Karzai is a hopeless and hapless leader. Given the factional war inside the administration, Karzai himself felt perfectly free to weigh in on the controversy let loose by the incendiary let-it-all-hang-out Rolling Stone article. Karzai let it be known he saw McChrystal as "the best commander the United States has sent to Afghanistan." The president of another country became a player inside our own country's political deliberations.

Paradoxically, Karzai's supportive comments underscored why McChrystal had to be relieved. One little-noted passage in Michael Hastings's Rolling Stone article underscored McChrystal's central problem. "The most striking example of McChrystal's usurpation of diplomatic policy is his handling of Karzai," Hastings wrote. "It is McChrystal, not diplomats like Eikenberry or Holbrooke, who enjoys the best relationship with the man America is relying on to lead Afghanistan. The doctrine of counterinsurgency requires a credible government, and since Karzai is not considered credible by his own people, McChrystal has worked hard to make him so."

A military strategy is supposed to fit the facts on the ground. But McChrystal was trying to invent an alternative reality to fit the facts to his counterinsurgency strategy, trying to turn Karzai into something he isn't. The open split on the American side has reduced Karzai's incentives to alter his behavior.

Then there was the breathtaking immaturity on display in the Rolling Stone piece, the kind of thing Gen. David Petraeus, his successor, can be counted on to avoid. There was also a profound contempt shown toward almost everyone outside McChrystal's tight inner circle. What signal did McChrystal think he was sending through Hastings? Worse still would be indifference on McChrystal's part to the potential impact of the article. The key to counterinsurgency strategy is its awareness of the effect of politics, governance and public opinion on the chances of success.

A piece of this sort was destined to undercut whatever McChrystal was trying to do, and the arrogance that came through in the article plays badly, given that McChrystal's military strategy has not seemed to work very well so far. But Obama is not off the hook. On the contrary, he stuck with McChrystal, despite ample evidence that the general would go around the White House to push his own preferences.

Moreover, Obama's approach to Afghanistan was always a delicate balance, a Goldilocks strategy that was neither too hawkish nor too dovish: Escalate now to speed withdrawal. It was a nice idea, and maybe it can still allow us to leave a modestly improved situation behind.

The problem is that this careful equilibrium required everyone in the administration to pull together, accepting that the policy was settled and was not open to constant challenge. It required very big egos to get along. It required Karzai to change. It required Obama to have real authority over our military.

Obama asserted that authority in a statement that was gracious but firm, and he reminded his fractious team of the importance of a "unity of effort." But he still needs to make his objectives clearer, beginning with an answer to the question: Are we serious about beginning withdrawals next July? Given what's happened so far, we should be. 

(c) 2010, Washington Post Writers Group

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