As U.S. military forces continue to stream out of Iraq, formally ending combat operations on Tuesday, one of the most effective elements of those forces missed the drawdown completely.
There are as many special operations forces in the country now as there were when the exit began last year.
President Obama, who as a U.S. senator opposed a 2007 troop surge and called for withdrawing all troops from Iraq, is set Tuesday to tell the nation that combat missions by Americans are officially over. There are now fewer than 50,000 American troops in Iraq, down from a surge-high of 168,000 in late 2007.
New challenges begin. An Iraqi security force of about 670,000 troops will have to shoulder the brunt of attacking insurgents, while Iraqi politicians seek an elusive deal to form a new parliamentary government.
"In reality, the Iraqis have been doing the majority of the security work for some time now," Army Gen. Raymond Odierno, the top U.S. commander in Iraq, told PBS last week. "And so I feel very confident that they will be able to continue. There will be ups and downs. There will be bad days, but they will continue to provide adequate security."
Prime Minister Nouri al-Maliki underscored the "bad days" on Sunday, as he put the fledgling democracy on its highest terror-alert level. Stepped-up attacks are expected from al Qaeda and groups still loyal to the Iraqi Ba'ath Party regime of Saddam Hussein to show that government forces cannot contain violence.
"The lack of a government obviously makes people nervous, and it provides some uncertainty," Gen. Odierno said. "But what I've been proud of is the Iraqis' security forces have remained neutral. They've done their job according to the constitution."
There is wiggle room in the status-of-forces agreement with Baghdad that was worked out in 2008, in the waning days of the George W. Bush administration. Pentagon officials expect some U.S. forces to remain, even though the agreement calls for all troops to be out of Iraq by Dec. 31, 2011.
Those holdovers may include some of the 3,000 Army Green Berets, Navy SEALs, Army Delta Force and other specialized warriors who remain locked in combat.
With regular U.S. ground combat brigades leaving, special forces commandos have become the key to successfully handing over all military duties to the Iraqis 15 months from now.
The commandos train Iraqis to do the jobs of American soldiers. They also make up joint terrorist-hunting units with government troops to rid the country of al Qaeda operatives tied to Osama bin Laden in Pakistan.
The U.S. no longer conducts any unilateral operations, said Army Lt. Col. Terry Conder, a spokesman for special operations force units in Iraq.
"There was no reduction of SOF during the drawdown," Col. Conder said. "The U.S. special operations mission has not changed."
Special operations troops working in the background have been credited with capturing and killing scores of al Qaeda terrorists in Iraq, including the 2006 raid that killed al Qaeda leader Abu Musab Zarqawi.
The burden is falling not only on special operators. The Iraqis will rely heavily on CIA officers, who will remain for the foreseeable future to help identify and eradicate insurgents.
A big part of the 2007 troop surge was an emphasis on intelligence collection to locate and then kill or capture insurgent leaders.
"Challenges are substantial, and I suspected they will increase," said Bart Bechtel, a former CIA operations officer in the region.
Mr. Bechtel said that if CIA officers lack protection from the U.S. military, it will be more difficult to find human intelligence sources.
"As we draw down our troops, one effect will be fewer eyes and ears on the ground and out in the countryside," Mr. Bechtel said. "I fear that [recruited spies and informants] will suffer greatly, if our intel collectors are significantly confined within the Green Zone. Already, there are substantial threats to any asset cooperating with the U.S. Those threats can only increase. Validating intelligence from human sources becomes more difficult if our officers are unable to get out amongst the population obtaining ground truth directly themselves."
He added that "a great deal will depend on how unstable the country becomes as we withdraw. Increasing instability means less freedom of operating. It is not impossible to operate in very hostile environments, it is just very limiting. I only hope that management [at CIA headquarters] in Langley, Va., and in the field do not become risk-averse to the extent that it is unwilling to do what is needed to succeed in our missions."
The State Department is taking steps to make sure its contingent of some 5,000 diplomats and staff is protected. It plans to hire more private-security bodyguards to replace its military protectors, in effect creating its own army of protectors.
And there is a second enemy: Iran.
Gen. Odierno said that Iran's intelligence and special operations agents continue to help insurgent Shiites launch attacks.
"I would just say they continue to be involved in violence specifically directed at U.S. forces, in direct-fire attacks, things like that," he said. "In some areas where there are some intra-Shia issues, I believe they're “¦ influencing some action by intimidation. So they are behind this. They are training people. They are supplying people with weapons. They continue to be involved in this."
John Pike, who directs Globalsecurity.org, said the challenges remain daunting, as they did before the surge.
"Iraq faces pretty much the same challenges post 31 August as it has for the past couple of years," he said. "Al Qaeda has not been suppressed, corruption is rampant, the political system is deadlocked, Iran has significant political influence, high levels of violence persist, their military remains incapable of either operating without U.S. support or defending the country against external enemies."
But Baghdad can persevere.
"Belgium's government is also deadlocked," Mr. Pike said. "Caracas has violence comparable to Baghdad, and yet the sun still comes up in the east every day. Seriously dysfunctional countries can muddle through somehow, even if they are not attractive vacation destinations."