Bush’s legacy is going to last a very long time, and it is not a pretty one. Once Hussein was out of Iraq, only some kind of highly functional secular state was going to keep its Shi’ite majority from falling into Iran’s orbit. The war and occupation and dysfunctional political state have wrought something pretty much the opposite of a highly functional secular state: its Shi’ite majority, long oppressed by Saddam’s Ba’ath party, are now very big fans of democracy and its inherent powers granted to majorities against minorities.
Iranian-backed militias were among the most effective fighters against Al Qaeda: the army was just seen as a way to make money, sell gear, and steal from the treasury… not at all a real fighting force, as opposed to the Shi’ite militias, who formed to fight, drill to win, and have a focused mission of retaking Iraq and making it Shi’ite. The army is still trying to disentangle itself from its corruption while US advisors try to help them, but Iran’s religious soldiers are proven and making things happen on the ground.
The end result isn’t here yet, but you can see it: Iranian influence from the Persian Gulf to the Mediterranean, by way of Iran-Iraq-Syria-Lebanon. Once Saddam fell, this was about the only way it could’ve gone, and this is where we are: Sunni Saudi Arabia is embroiled in a regional competition with Shi’ite Iran and engaging that competition by starving Yemen with US weapons, meanwhile Iran is liberating Iraq.
It’s an all-too-predictable disaster that American hubris forged. It was repeated on a smaller scale in Libya, with none of the lessons learned there, either… the saving grace there being that there are no nearby regional powers strong enough to take advantage of the chaos, only ISIS living in the cracks of destruction.
There’s something about having all this money and gear to burn on weapons and war, seemingly totally divorced from the average American’s experience of war that makes us do astoundingly dumb things. My guess is that there’s often no significant blowback: the voters don’t care that much about endless war or domestic surveillance, the Treasury and Congress always seems to have more money for war, and everything awful is happening Over There (1M starving in Yemen as of today, and for all the noise and money about ISIS they’re operating out of pick up trucks).