It turns out that a war exercise in 1999 simulating an invasion of Iraq foresaw a range of problems that have in fact popped up. And that report was the first one to recommend that 400,000 troops be used as an occupying force (and even that number was considered only what would give the transition in Iraq a chance to work, still not a sure thing), a recommendation which was repeated directly to Donald Rumsfeld and George Bush by general Eric Shinseki prior to the Iraq war. Of course as we know Rumsfeld effectively silenced any further recommendations on the matter by drumming Shinseki out of the army for daring to make such a recommendation contrary to the 'Rumsfeld doctrine' of cheap, light forces being used for occupation.
From the report:
"A change in regimes does not guarantee stability," the 1999 seminar briefings said. "A number of factors including aggressive neighbors, fragmentation along religious and/or ethnic lines, and chaos created by rival forces bidding for power could adversely affect regional stability."
"Even when civil order is restored and borders are secured, the replacement regime could be problematic -- especially if perceived as weak, a puppet, or out-of-step with prevailing regional governments."
"Iran's anti-Americanism could be enflamed by a U.S.-led intervention in Iraq," the briefings read. "The influx of U.S. and other western forces into Iraq would exacerbate worries in Tehran, as would the installation of a pro-western government in Baghdad
Over the past year or so we have seen Bush/Cheney/Rumsfeld assert that the situation in Iraq has not gone as expected.
No, it has not gone as THEY expected. It has gone exactly as the military analysts who modeled it in 1999 expected.