"If your assesment of the tri-dependency holds true, then all will be well. If it does not turn out to hold ground, and that does not mean what you said is inaccurate by any means, then other scenarios could develop. And is essentially what I brought out in my dooms day approach. I surely hope what I wrote does not come to past. But I think it could given forces we may be overlooking. What they are, not sure. Because again, I can believe the Shia may not want to play a nasty game on the Sunni. Just keep them under wraps. For which one cannot blam them. Let me conclude with just this note. We probably agree that both Sadr and Hakim are both in the sack with the Iranian Mullahs to some extent. To much has been written as how they cohort together, pay visits to Iran etc..." 
Right. Don't get me wrong, civil war is a possibility when you go blow up a strong central government that has been "keeping the peace" via military force.
What we have to ask is why the Kurds didn't immediately declare independence in April of 2003...why the Shia didn't go for Sunni blood by May of 2003, and why the Sunnis are finally voting in Iraqi elections.
...And when I answered those questions in the posts above, I saw that there are some very powerful carrots and some very grave sticks that are in play.
The Kurds want U.S. protection from the Turkish Army. The Kurds want Iraqi oil and Iraqi political power and a nearly-autonomous region of "Iraq" for themselves.
Well, by playing ball with the U.S., with the new Iraqi government, the Kurds get all of that while avoiding a war with Turkey.
The Arab Shia gain control of Iraqi politics, of global Shia politics/holy sites, Iraqi oil, a prestigious place on the world stage, as well as U.S. protection from Persian shia...all for playing along with the U.S. plan and the new Iraqi government.
The Sunnis in Iraq gain an over-representation of their numbers in the new Iraqi government, a share of Kurdish and Shia oil that they'd otherwise not have, and U.S. protection from Kurdish/Shia slaughter of their ranks for playing along.
These aren't just financial or prestige types of carrots...these are also life and death of entire culture issues. Sticks. Big sticks. Carrots. Rich carrots.
And this is why civil war hasn't broken out all across Iraq en masse. Well, that plus outstanding geopolitics by the Bush Administration and an amazing military presence on the ground and in the skies over Iraq.
President Bush is going for a long-term solution to terrorism. Root causes in Afghanistan, Libya, Lebanon, Liberia, and Iraq have been addressed both for the short term as well as for the long term in a variety of ways (e.g. national alignments, democratic republics, constitutions, military training, infrastructure rebuilding, educational and medical assistance, etc.).
There are over 1,000 UAVs flying over Iraq today. Iraqi ground forces can call for these U.S. aircraft to strike targets on the ground. This gives Iraqis control, yet also builds their trust and appreciation for the U.S.
It's not quite a dependency...it's more of a bonding much like what individual soldiers experience in their units after their first combat.
Saddam is jailed. The UN sanctions on Iraq are lifted. Military, economic, and infrastructure aid is being given. Individual Iraqis can hold political office without debts of blood and bribes. International trade is legal for Iraqis now.
These are massive developments that Iraqis couldn't experience prior to 2003, and I suspect that they'll be more grateful to the U.S. over the long term than that of several countries that we liberated circa 1944/1945.
Such an eloquent follow up cannot be ignored.
I have of lately made a course changed primarily based on news coming out regarding the Iraqi horse trading, or what could be perceived as lack of. Up till a few weeks back my statements have very much mirrored what you write. Just on the Kurdish scenario one can see the wisdom in the approach you take. The Kurds can have their cake and eat it to providing they play their cards carefully.
And if the day Iraq would become a candidate or accepted member of NATO, then the Kurds have even less fear from the Turks from a national view point. For many reasons either of us could elucidate on. Likewise, the Arab Shia, would be protected from further Persian influences in it's many forms. Many folks do not appreciate most of the Shia clergy in Iraq do not take marching orders from the Iranian Mullahs. And though say the Grand Ayatollah Sistani has roots in Persia, he left long ago because he did not see eye to eye with the Revolutionary Guard and Mullahs in general. And obviously is on record for clergy to stay out of politics.
As for the SCIRI's Abu Aziz Al-Hakim, and Muqtada al Sadr's backing of the NIC and UIA in general, they have displayed different resistive styles and represent different bodies of Arab Shia in Iraq. In short, they back say Ibrahim al Jaafari for different reasons that fit into their political/patriotic/religious psychic.
But by all indications none want to hold allegience to the Persian Grand Ayatollah Seyyed Ali Hosseini Khamenei.
So again. I am in agreement with your assesments as to why the three main Iraqi ethnic/religious groups have good reasons to not want Iraq to split up. It would put each at a distince disadvantage in relation to Iraq's neighbors.
Only an Iraq fully united will eventually benifit all Iraqis. And surely these horse traders must lay awake at night wondering just who the new Iraqi army would back if it where to stay united as one, if the country where to be divided.
So in summary. Perhaps my course change deals more with playing devils advocate, as well as pondering on reasons to surface as to why the horse traders are not at this point, based on the over all conditions, giving a little more to arrive at a balanced elective body. As Omar at ITM worries of lately, why are these leaders not yielding more to the realities/needs to form a stable government that will with the army and police forces show a united front against all the sectarian divide as well as the remaining insurgents both local and foreign. He obviousely groans in the spirit when he had talked about this new proposal for a National Security Committee, being purely a smokescreen.
It detracts from the energies required for the Interim Election Assembly to stay focused on the task at hand. That being bringing forth the final pick of future leaders, for vote and swaring in.
I just think they are all so bogged down, in petty quarrels and short term gains, that they refuse to admit the bigger picture is required for their mutual survival, assuming in their minds survival means a strong Iraq under a central government that will move Iraq forward both politically, industrially, and econonmically within the framework of a seculare framework of goverance. Put another way. Many of them just cannot see beyond their nose. They are stuck in the past. And they are not ready to take the really great leap in faith, mostly based on their lack of edcuation in westernized democratic governments. So they continue to horse trade, or lack of it, and bid their time, much like many of us may do, concerning a tooth that has to be pulled.
Do not feel obligated to respond. Surely what I write must be a generic concern many would adhere to, at least in principle. But do add if required.