The key tribal chief responsible for the only core success in Iraq these past few months has been assassinated. Who did it? Some analysis:

Nothing could have been more predictable than the murder of Abu Risha, the man most closely identified with America's Anbar strategy. He was the public face of the turn against al-Qaeda, and Petraeus immediately said that "it shows Al Qaeda in Iraq remains a very dangerous and barbaric enemy."  But there's no reason to assume that al-Qaeda killed him - I'd guess that one of the nationalist insurgency groups, the ones which current American rhetoric pretends don't exist -  is a more likely suspect.  Other tribes deeply resented him….

His murder graphically demonstrates that the other groups threatened by the American Anbar strategy were never going to just sit back passively and allow it to succeed - an obvious strategic point which has always seemed to elude surge advocates.  The Sunni strategy as presented by surge advocates has always rested not only on a whole series of dubious claims about Iraqi Sunni politics, but also relies on a whole series of best-case scenarios in which nothing could go wrong.  In Iraq, something always goes wrong.

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