IMHO, that's the takeaway from the long corporate-style document called "Learning from Iraq: A Final Report From the Special Inspector General for Iraq Reconstruction."
You can read the IG report online in its entirely here: http://www.sigir.mil/learningfromiraq/index.html.
But if you've read Peter Van Buren's We Meant Well: How I Helped Lose the Battle for the Hearts and Minds of the Iraqi People, you already knew.
