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BAGHDAD, Iraq (CNN) -- Without doubt, the surge has benefited Iraq. It's massively reduced the killing of both Iraqis and Americans, and it's been a welcome relief to witness the change.
I first saw it last year on the streets of Ramadi, former insurgent and al Qaeda stronghold. On my previous visit in 2006, the Sunni-dominated city was one of the most dangerous places for U.S. forces in Iraq. Foot patrols were unthinkable. In May 2007, I walked the back alleys and markets with U.S. Marines, and could feel the change.
But to credit the change to the surge in troops would be to miss other important factors.
Months before the surge began, tribal leaders who had long worked as local arbiters of justice found their tactic of supporting insurgents was failing. Al Qaeda was sucking power away from tribally influenced insurgent groups who were fighting on nationalist and religionist agendas. When the tribal leaders realized this, they saw the United States as a potential ally to fight off al Qaeda and get back their traditional power broker role.
The United States cemented the new relationship by rewarding these same tribal leaders with lucrative business contracts that would benefit the community. It was a marriage of the most important convenience. Tribal leaders diverted their insurgent followers to new local neighborhood defense groups -- in effect, local militias sanctioned, supported and funded by the U.S. military.
More security meant fewer attacks. In many cases, the attackers were now the security forces. What America had done was a massive reversal of previous policy, which did not allow local militias, nor of working with their former killers. It's a measure of how bad things were and of how few Iraqi security forces there were in Anbar, the province with Ramadi as its capital. But it worked to a point.
In Baghdad, the surge worked in a similar way. Local communities were allowed to stand up their own "concerned citizens groups" to defend their neighborhoods. Surge soldiers moved out from their big bases in to the community. This helped the community groups by surrounding neighborhoods with blast walls isolating Sunni from Shia. Attacks fell and as they did Shia cleric Muqtada al-Sadr, whose Mehdi Army was blamed for some of the worst sectarian bloodletting and attacks on U.S. troops, called a cease-fire last August.
I remember in September 2007 being told by two Iraqi ministers that if politicians did not grasp the lull in fighting to bridge their political differences, the killing would return -- possibly on an even more deadly scale.
Behind the scenes the militias have been rearming. They are now better organized and better trained than ever before. So as the surge draws down, where do we stand now? The prime minister has gone on the offensive against al-Sadr's militia. Iraq's security forces are still far from ready. American commanders say the risks they face of backfilling their troops with Iraqi soldiers is manageable. The potential for a slip back to massive violence is real and a thinner force will be no match.
Historically, the world over, militias affiliated with political or tribal leaders rarely disarm. They are persuaded by time or inducements that there is no need to fight. They keep their weapons but are motivated not to use them. Iraq is far from that point. Sectarian tensions simmer, blood feuds are far from settled and ethnic and economic differences still lack resolution. I sense some U.S. commanders are holding their breath hoping the surge draw-down works.
What many tell me they don't want is for the blood and lives already given to be in vain. The surge gave the narrowest of margins for improvement. Look at Mosul: when the surge in the south left them short, al Qaeda regrouped there and is re-emerging. The country is still on a knife edge, possibly slightly blunter but a fall on either side is nonetheless deadly. E-mail to a friend