Baghdad, Iraq ? The Bush administration’s decision to move thousands of U.S. soldiers into Baghdad to quell sectarian warfare before it explodes into outright civil war underscores a problem that’s hindered the American effort to rebuild Iraq from the beginning: There aren’t enough troops to do the job.

Many U.S. officials in Baghdad and in Washington privately concede the point. They say they’ve been forced to shuffle American units from one part of the country to another for at least two years because there haven’t been enough soldiers and Marines to deal simultaneously with Sunni Muslim insurgents and Shiite militias; train Iraqi forces; and secure roads, power lines, border crossings and ammunition dumps.

Although military planners are still finalizing the details, as many as 4,000 additional U.S. soldiers are being sent to Baghdad, including two battalions of the Army’s 172nd Stryker Brigade, four or five military police companies from northern Iraq and a field artillery battalion that’s standing in reserve in Kuwait.

But when U.S. forces have cracked down in one place, Iraqi insurgents and foreign terrorists have popped up in another. Some towns have been pacified multiple times, only to return to chaos as soon as the Americans reduced troop numbers. In cities such as Baghdad, Kirkuk, Samarra and Ramadi, bloodshed ebbs and flows, but security is never a given.

The frustration of returning to quell violence in the same places multiple times has taken a toll on American morale, undermined Iraqi confidence in the U.S. and cast doubt on the Bush administration’s hopes of beginning significant withdrawals of soldiers and Marines by the end of this election year. There are 130,000 U.S. service members in Iraq, down from 160,000 in December.

“This is exactly what happens when there aren’t enough troops: You extend people and you deplete your theater reserve,” said an American defense official in Iraq, who spoke on the condition of anonymity because of the sensitivity of the topic.

A U.S. Army 1st Battalion, 24th Infantry soldier walks ahead of an armored Stryker combat vehicle in 2005 in Mosul, Iraq. The U.S. top commander in Iraq, Gen. George W. Casey Jr., confirmed Saturday the Army will send about 3,700 troops to Baghdad to try to quell violence, which many officials find troubling.

During embedded reporting trips beginning in the summer of 2003 – which included time with troops from eight Army divisions, an armored cavalry regiment and several Marine units – a McClatchy reporter was told repeatedly that more manpower was needed.

American officials in Iraq and in the United States said the shortage stemmed from a number of factors, including:

¢ Defense Secretary Donald H. Rumsfeld’s belief that a small but agile, high-tech American force could topple Saddam’s regime, in part because Iraqi exiles had assured the administration that American troops would be greeted as liberators. From the beginning, a number of U.S. officers said, senior White House and Pentagon officials said that post-invasion Iraq would require fewer than 200,000 troops.

¢ The decision early in the American occupation of Iraq, also encouraged by Iraqi exiles, to disband the Iraqi military. This deprived the U.S. of some potential Iraqi allies and drove some Sunni soldiers and officers into the insurgency.

¢ Rumsfeld’s reluctance to increase U.S. deployments in Iraq or the overall size of the Army despite the escalating violence. “It could be two divisions-plus just to secure Baghdad, and you’re talking a 10-division Army,” said a senior American military official who served in Iraq and is now in the United States.

¢ The inability or unwillingness of many newly trained Iraqi forces to take over security from the Americans or even to operate independently, which has dashed the administration’s hopes that U.S. troops would stand down as the Iraqis stood up.