This story is pretty disturbing, although it basically says things we knew before. Basically Rumsfeld and the Pentagon were so self-absorbed int heir own vision of things that they were completely blinded to contrary input coming from elsewhere. And not just from the "opposition" but by the State Department and CIA.
AFP on Yahoo News
Pentagon planners failed to develop detailed plans for postwar Iraq because they were convinced Iraqis would welcome US troops and that a hand-picked exile leader would replace Saddam Hussein and impose order.
...
Postwar planning documents from the State Department and the CIA were "disappearing down the black hole" at the Pentagon, a former US official was quoted as saying.
For example, the Pentagon ignored the "Future of Iraq" project, an eight-month effort by the State Department involving 17 agencies and dozens of exiled Iraqi professionals.
Officials in the Pentagon's Near East/South Asia bureau, which houses the Office of Special Plans, were told to ignore State Department views, according to Air Force Lieutenant Colonel Karen Kwiatkowski, who retired from the bureau July 1.