What’s interesting is the timing of when he resigned in Oct 2007; it was after the summer where the insurgency took a beating and was really faltering and it looked like the war was essentially going to be won; al Dhouri of the Baath insurgency began denouncing al Qaeda and was inquiring about negotiating, and the Dems were looking at gaining congress and being in position to saboutage the war in Iraq and force a loss while Bush was still president.
The Dems gained control in Jan 2007.