It's so amazingly rare that Biden gets anything right, but yes... those are two points to which I wish Bush had listened. Three homogeneous countries within, say, a loose Iraqi federation could've formed their own governments, with their own militaries, and pursued their own goals. Trying to keep stitched together an artifically formed Iraq was folly.
I was just thinking about that last night. As much as I hate to give Biden the time of day he was prolly right about establishing a 3 region coalition. Even a blind bird gets a worm once in awhile.
The problem there, is that the government envisioned the new Iraq after US occupation ended as being a strategic counterweight to Iran, as it was in the 1980s. A divided Iraq couldn’t serve that role.