Is al-Qaeda in Iraq a Myth?

At The Washington Monthly former Stars & Stripes reporter Andrew Tilghman has a potentially explosive piece on what the title calls the "Myth" of al-Qaeda in Iraq. He concludes his piece thusly:

Five years ago, the American public was asked to support the invasion of Iraq based on the false claim that Saddam Hussein was somehow linked to al-Qaeda. Today, the erroneous belief that al-Qaeda's franchise in Iraq is a driving force behind the chaos in that country may be setting us up for a similar mistake.

I have tended to be wary about underestimating al Qaeda's will to do the liberal west harm even if the organization does not have the capacity to carry out its most ardent desires. But I think we do need an honest an open debate about causation and correlation in Iraq, about al Qaeda's real role throughout the conflict there, and about the various options and consequences for each of them. There is no ideal result about to spring forth like a mirage from the desert sands. But there surely are better options, and those are what we have to seek.