If there is a civil war emerging in Iraq then it represents a turning point.

One conception of a potential 'civil war' is that it would probably result from the antagonisms between the Sunnis, Shiites and Kurds. That was the view of public opinion last year. It suggested a federal kind of democracy to contain the different ethnic voices since Iraq is a cobbled together nation state.

That was last year. It looks different now. An emerging civil war looks as if it tmay result from being provoked by the U.S. occupation authority, and waged by its forces against both Sunni's and the growing number of Shiites who support Muqtada al-Sadr. A civil war that has the potential to become a war of national resistance to a foreign occupying power. That means a black hole.

In that context this article by William Safire from the New York Times makes for sobering reading. His line is crack down harder.

"But now that the Saddam restorationists and Islamic fundamentalists have made their terrorist move on both fronts, we can counterattack decisively."In war, resolution." Having announced we would pacify rebellious Baathists in Falluja, we must pacify Falluja. Having designated the Shiite Sadr an outlaw, we must answer his bloody-minded challenge with whatever military force is required and with fewer casualties in the long run.
But we must impress on the minds of millions of Shiites that there is no free ride to freedom."

"We should couple this with a temporary increase in troop strength, if necessary: we will pull alongside, not pull out or pull alone. We should take up the Turks on their offer of 10,000 troops to fight on our side against two-front terror. The Kurds, who have patched things up with Ankara and know which side of the two-front war they and we are on, would withdraw their ill-considered earlier objection."

That may well draw the Americans deeper into the abyss by triggering an enormous backlash. This is argued by Christopher Layne:

"...the coercive use of US military power is bound to trigger an enormous backlash. US military power won't stop armed Iraqi opposition to the occupation – it will fuel it. Here, the US finds itself facing the classic dilemma of colonial powers when indigenous populations challenge outside rule. Repression does not stop anti-colonial nationalism, it just creates an upward spiral of violence. And colonial powers always reach a point where the costs of staying exceed the risks of withdrawing."

Layne goes to say that:

"... Iraq is not going to be stabilised any time soon, least of all if the US remains as a colonial power. Iraq is not going to become a Western-style democracy (and, if by some miracle it did, it would be an anti-American, anti-Israeli democracy). "

Staying on will not make things better. The resistance to the US-led occupation will grow and Iraq will become a magnet for Islamic fighters who want to take on the US.