(CNN) -- We can spend the next few years beating ourselves up and debating the proposition that George W. Bush saved Iraq and Barack Obama lost it. Or we can get real and try to sort out what we can do now to protect U.S. interests in a region that's melting down. Iraq was never the U.S.'s to win. That point -- along with lowered expectations and focused goals -- must be the basis of any new approach to the region. And here are three reasons. 1. Demography: There are two factors that nations -- even functional ones (and Iraq is not) -- can't alter: What they are -- their demography; and where they are -- their geography.
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Aaron Miller: Debating what went wrong in Iraq not useful; protecting U.S. interests now is
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Iraq is complex, he says, with sectarian groups at odds, neighbors with own interests
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He says U.S. must work with Iraq's neighbors, even al-Assad, to halt ISIS. Democracy can wait
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Miller: U.S. must help right Iraqi military, but without combat forces. Point is to check terror
@placeholder's own ideology will produce a counterreaction among Iraqis who will oppose its harsh, unforgiving ideology.