Major Ben Connable, USMC writing in the NY Times today gives the cost both to the US and the Iraqis:

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... What will become of Iraqi villages, towns and cities as we pull out? Although past is not necessarily prologue, recent experience in Anbar Province may be instructive.

American units have already withdrawn from the western Euphrates River valley — twice, in fact. As the insurgency heated up in early 2004, the Seventh Marine Regiment pulled up stakes and went to fight insurgents in eastern Anbar, leaving the rest of the province in the hands of a battalion of troops. The Marines balanced obvious risk against the possible reward of overwhelming some of the insurgent groups in the east.

The consequences were immediate and bloody. Insurgents assumed control of several towns and villages. They tortured and executed police officers, local politicians, friendly tribal leaders and informants. They murdered contractors who had worked with the Americans or the Iraqi government. They tore down American-financed reconstruction projects and in a few cases imposed an extreme version of Islamic law. Many Iraqi military units collapsed in the absence of United States support.

The insurgents celebrated their self-described victory and exploited the withdrawal for propaganda purposes. Baathist-led insurgents used the opportunity to establish training camps and weapons caches in the farmland and along the river banks while other groups, including Al Qaeda, smuggled in fighters, suicide bombers and money to support operations in Ramadi, Falluja and Baghdad. Western Iraq became a temporary haven for criminals, terrorists and thousands of local thugs who made up de facto mini-regimes in the absence of a stabilizing force.

When the Seventh Marines returned to western Anbar it was essentially forced to retake some of the towns it once controlled. Many local Iraqis were openly hostile; the battle for the hearts and minds of the population was set back months, if not years. With the politicians murdered, local civil administration was almost nonexistent and any influence held by the central government was lost.

The Seventh Marine Regiment pulled up stakes again in November 2004 to join the second fight for Falluja. Conscious of the damage done by the earlier withdrawal, the Marines left behind more troops in an effort to stem the inevitable surge of insurgent and criminal gangs; Iraqi forces were not yet ready to assume control.

Despite this Marine presence, the results were similar. What had been rebuilt in the summer crumbled in the fall.

The two withdrawals left the western Euphrates River valley in a shambles. At the end of 2005 the Marines were forced to conduct sweep and clear operations from Anbar’s capital, Ramadi, to the Syrian border town of Husayba. As they pushed west they uncovered hundreds of weapons caches, elaborate insurgent propaganda centers, carefully camouflaged training camps, suicide vehicle factories and complex criminal networks that were feeding a steady stream of money to insurgents and terrorists across the country. Marine units settled back in, spread out and brought attack levels to unprecedented lows.

Since 2005, the situation in Anbar has significantly deteriorated. But as bad as things have become, American and Iraqi forces retain some degree of control in even the most turbulent areas. The border cities of Husayba and Qaim are relatively stable and have effective security and government. Falluja, also stable, is a model for Iraqi-American military cooperation. Advisers are embedded with Iraqi units across the province. American-supported tribes are beginning to combat Al Qaeda in Iraq in the east. Anbar is down but not out, thanks to the American troops along the Euphrates River.

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While Major Connable is making the case against a quick withdrawal of forces he is also showing the high price of having to pay for the same real estate more than once. We had to pay that price because we had an inadequate force to space ration in the area he is talking about. Regardless of the fact that we had adequate combat power to defeat the enemy each time, the cost kept getting higher each time. Having an adequate number of troops to take and hold the area would have saved lives and made it much more difficult for the enemy to survive. The way you defeat an enemy that uses a raiding strategy is by having a sufficient force to space ratio to stop his ability to move to contact. It also gives you the ability to destroy his sanctuaries, thus putting him in motion where he is most vulnerable. The whole article is worth reading.