Of course, that went hand-in-hand with the excesses of de-Baathification; purging every single member of the party, irrespective of rank, from the civil service, which ended up amounting to up to 100,000 people. Besides the serious diminution of state capacity this effected, it alienated, and deprived of their livelihoods, much of what was the Iraqi middle class. I mean, the state collapse in Iraq can rather plainly be traced to the gutting of the state by the provisional authority. This is particularly bizarre, as we had learnt the perils of such an approach in Germany and didn't even try it in Japan.
The failure of the US to achieve its goals in Iraq had less to do with the goals themselves as opposed to the people who were entrusted to carry them out. The Bush administration gave the provisional authority an alarming degree of latitude in hastily determining policy, who in turn gave much credence to people like al-Jafari or Chalabi (who arguably got us into this whole mess). It goes back to the disinterest that administration officials had in planning for the post-war reconstruction process. Which, I suppose, stemmed in turn from the naive neo-conservative belief that the Iraqi people would embrace "democracy" eagerly and quickly resolve their problems on their own.
Agreed that Bremer made serious errors with the Iraqi Army and the de-Baathification. However, juxtaposing ISIS and the Sunnis like this conflates the two. Like Al Qaeda in Iraq and al Zarqawi before it, your standard Sunni/ex Baath and are using ISIS to achieve their means. You could easily see more awakening councils once the dust settles. yet, they would be well advised to choose their allies wisely because ISIS cannot be tamed easily. They are wide eyed fanatics who will not listen to reason and do not want a peace, with justice or otherwise.