Some of the troops demanded by Generalissimo Field Marshal Fred Kagan will start returning home this month.

WASHINGTON - The first big test of security gains linked to the U.S. troop buildup in Iraq is at hand. The military has started to reverse the 30,000-strong troop increase and commanders are hoping the drop in insurgent and sectarian violence in recent months - achieved at the cost of hundreds of lives - won't prove fleeting.

The current total of 20 combat brigades is shrinking to 19 as the 3rd Brigade, 1st Cavalry Division, operating in volatile Diyala province, leaves. The U.S. command in Baghdad announced on Saturday that the brigade had begun heading home to Fort Hood, Texas, and that its battle space will be taken by another brigade already operating in Iraq.

Between January and July - on a schedule not yet made public - the force is to shrink further to 15 brigades. The total number of U.S. troops will likely go from 167,000 now to 140,000-145,000 by July, six months before President Bush leaves office and a new commander in chief enters the White House.

It will be interesting to see whether the resistance picks up again after the short cessation of activity. Some cautious observers have maintained that the so-called surge was really designed to shoehorn more troops into Iraq in case there was a sudden need to have combat stiffeners in-country to push back against an anticipated ground response from the Iranian Army after that country’s facilities were bombed, as demanded by Dick “dick” Cheney and the Likud Party.

Some pundits have insisted that the so-called surge has accomplished its mission of quieting the civilian population although one can equally argue that the ethnic cleansing of Baghdad has been completed and that is the cause for the slightly lower civilian death tolls.

Declines in Iraqi civilian and U.S. military casualties in the past few months and talk among U.S. commanders of an emerging air of optimism and civic revival in some Baghdad neighborhoods point to positive security trends.

A key question is whether security will slip once U.S. lines thin and whether Gen. David Petraeus, the top U.S. commander in Iraq and orchestrator of the counterinsurgency strategy, has made enough inroads against insurgents - and instilled enough hope in ordinary Iraqis - to make the gains stick.

Others, more cynical, have felt that the sharply rising US casualties were creating a domestic political situation that was untenable for the Republican Party and that the Bu$h malAdministration had to appear to be doing something in order to keep frightened Republican politicians from bolting in order to save their seats in the 2008 elections.

Stephen Biddle of the Council on Foreign Relations, who just spent 10 days in Iraq assessing the situation for Petraeus, said a key reason for recent security gains is the emergence of the local anti-insurgent alliances - not just in Anbar province where they began early this year but also now in and around Baghdad. A key to sustaining those security gains will be the U.S. military's ability to police those alliances, he said.

"It's happening on a large scale basis throughout much of the country," Biddle said in an interview Friday. "The problem is how do you keep them from either turning sides again or from going to war against each other."

Some might ask why these alliances must be “policed” if they are based on a sort of ideological or political basis of true anti-insurgency. Wouldn’t the proper motivation be self-interest and survival? If these various groups like the Anbar Awakening are merely marriages of convenience they will melt away as soon as the tap of ready Occupation cash is turned off.

Brig. Gen. Stephen Gledhill, the second-in-command for training Iraqi forces, says he is confident that conditions have improved to the point where the Iraqis are capable of filling any U.S. gaps.

"Our answer is that they not only will be able to - they already are, and will continue to do so as they gain experience, capabilities and capacity, and not only here in Baghdad but all around the country," Gledhill said in an e-mail.

Counting on the Iraqis to take over security was at the center of the U.S. strategy before Petraeus took over in February for Gen. George Casey. In a change of emphasis, Petraeus put a higher priority on securing the Baghdad population while continuing to develop Iraqi security forces.

I don’t see why the 140,000 odd Iraqi security forces wouldn’t be ready to take up the slack. After all they’ve had four years of training by the Most Powerful Army in the World™ Right? Anyone?

And once they’ve proven themselves in combat it seems likely we’ll be able to withdraw our forces from Iraq, thereby finally putting an end to the damned lies and calumny that our invasion and conquest of Iraq was merely to steal their oil.

Right?