Four scenarios are presented by Mother Jones Magazine about what would happen if and when the US pulls out of Iraq. A full scale civil war, a civil war of that declines and fizzles out, a partition with ethnic cleansing/displacement or a negotiated settlement. The article is written by Robert Dreyfuss and explains the situation as well as anything I've read so far.
The step in the full scale civil war where the neighbors jump in seems to me to be missing motivation. Iran has plenty of troops on the ground already in the militias trained by the Iranian Republican Guard. Some trainers, some people to coordinate weapons transfers, maybe but that's already happening. Iran has no reason to put Iranian ground troops into a situation where Iran's team already has a decisive numerical advantage.
The Saudis don't have ground troops. That's how pathetic they are. Syria has, but it isn't jumping in to fight Iran. Turkey, if it was to go in to fight the Kurds wouldn't have any problem with either Iran or Saudi Arabia. But Turkey isn't capturing and trying to hold land in the mountains. It would at most do what Iran is doing, send weapons and advisors to make sure Kurdistan is as weak and isolated as possible, ultimately to force the Kurds to accept non-independence in an Iraq that would be willing and able to act against the PKK.
Dreyfuss assigns a 10 percent possibility to regional war. That is his least probable outcome, I agree that it is the least likely but I can't see how it would get even two percent as a possibility. But there isn't much practical difference in assigning 1 percent and assigning 10 percent on an event in the future. The message is that it is unlikely.
I have two favorite quotes from the article:
Who's Pushing It: Much of Washington conventional wisdom outside the Bush administration has coalesced around partition; proponents include Senator Joe Biden (D-Del.), Leslie Gelb of the Council on Foreign Relations, Kurdish adviser Peter Galbraith, and Pauline Baker of the Fund for Peace.
How to Make It Happen: Keep arming Sunni tribes, Shiite-dominated security forces, and Kurdish militias, ensuring that each is just strong enough to hold at least a chunk of the country.
... ... ...
... The resulting government coalition is both anti-American and anti-Iranian. It ruthlessly crushes Al Qaeda in Iraq and persuades the Kurds to accept limited autonomy rather than independence.
Who's Pushing It: Minus the anti-Americanism, a version of this scenario is the administration's stated goal—though actual policy undermines it at every turn.
Dreyfuss' construction "both anti-American and anti-Iranian" has a smidgen of truth, but is misleading. In practical terms, the resulting government coalition will participate in regional foreign policy matters consistently on Iran's side. Israel goes to war with Lebanon? Egypt and Saudi Arabia are muted? Sadr and the Baathists are loudly and opening condemning Israel, competing with each other to hold the biggest rallies supporting Lebanon, applying what diplomatic pressure they can muster and allowing weapons transit from Iran to Syria. Sanctions against Iran? After what Iraq went through with sanctions? You have to be kidding. Iraq would adopt a sanctions policy, at best, of don't ask don't tell.
So the resulting Iraq from negotiations would be anti-Iranian in that it would not allow Iranian agents to track down and kill Iraqi officers from the Iran-Iraq war. Other than that it would be with Syria, the most pro-Iranian country in the region.
The same scenario but that actually is pro-US, anti-Iran? Nobody in Iraq wants that. It just is not conceivable. It is not listed as one of Dreyfuss' four plausible scenarios for good reason.
Which leaves partition.
The US is officially opposed to it, but in order to get it, the US has to continue its current policies. Hmmm. Outside the Bush Administration, Washington openly advocates it. It is safe to say that the Bush Administration is lying in its claims to favor a negotiated unified Iraqi state.
I'll leave by noting that Baghdad is 6000 miles from Washington. A negotiated anti-US settlement could be achieved with far less loss of US lives, would not jeopardize the US relationship with Turkey which is kind of important and for the Saudis is preferable to partition.
This outcome would be bad for Israel, but other than hampering the US role as protector of Israel, it is impossible to see how this outcome in any way directly harms US interests. It clearly, just considering US interests, is not worth the cost the US will spend to prevent it.
This outcome, from the US strategic point of view, is essentially the same situation as prevailed before the invasion. That situation, like this one, was bad for Israel, not directly bad for the United States. Then as now, there were attempts to claim it was really done for the Saudis, not for Israel, but the Saudis openly and publicly said they preferred to leave the situation as it was. Israel's leaders and population openly and publicly favored an invasion.
Instead the US wants and is working towards a partition of Iraq on Israel's behalf. The US is going to get what it wants, but it is going to pay a very high price for it.