I disagree on two main points:
Mr. Bush never understood the complex history of Iraq (particularly the epic ethnic tensions he was walking into)...
Bush is a history major. Of course he understood the complex history of Iraq; he's got a bachelor's degree in History from Yale. Oh, right.
...the tragedy of George Bush is ultimately one of his own making, and one that he cannot readily extricate himself from...
No, Bush'll be able to shake this one off too. He always has. And he'll always have a loyal cadre of "dead enders" who will believe in him until the end. He'll do what a good confidence man always does: make excuses and walk away without a scratch. Not to mention millions in appreciated oil stock.