CAMP ANACONDA, Iraq (AP) – Spc. Chris Carlson had been out of the U.S. Army for two years and was working at Costco in California when he received notice that he was being called back into service.

The 24-year-old is one of thousands of soldiers and Marines who have been deployed to Iraq under a policy that allows military leaders to recall troops who have left the service but still have time left on their contract.

“I thought it was crazy,” said Carlson, who has found himself protecting convoys on Iraq’s dangerous roads as part of a New Jersey National Guard unit. “Never in a million years did I think they would call me back.”

Although troops are allowed to leave active duty after a few years of service, they generally still have time left on their contract with the military that is known as “inactive ready reserve” status, or IRR. During that time, they have to let their service know their current address, but they don’t train, draw a paycheck or associate in any other way with the military.

But with active duty units already completing multiple tours in Iraq, the Pentagon has employed the rarely used tactic of calling people back from IRR status, a policy sometimes referred to as a “backdoor draft.”

According to the U.S. Army Reserve, approximately 14,000 soldiers on IRR status have been called to active duty since March 2003 and about 7,300 have been deployed to Iraq. The Marine Corps has mobilized 4,717 Marines who were classified as inactive ready reserve since Sept. 11, and 1,094 have been deployed to Iraq, according to the Marine Forces Reserve.

The 1st Squadron of the 167th Cavalry RSTA, which is based in Lincoln, Neb. and oversees the New Jersey guard unit here in Iraq, has about 40 IRR soldiers within its ranks of roughly 1,000 soldiers, and officers in the squadron say the troops have merged into the unit without any problems.

Jason Mulligan, 28, of Ridgefield, Conn., left the army back in 2002 after two years in the infantry. He was working as a painting contractor while studying wildlife conservation when he received his letter last fall alerting him that he’d been mobilized.

The letter was followed up by another warning to Mulligan that if he didn’t comply, the government would prosecute him to the fullest extent of the law.

“My family and my fiancee were telling me ‘Don’t’ report. Don’t show up,’ said Mulligan, who also serves with a New Jersey National Guard unit as a gunner on a Humvee helping patrol the territory around Camp Anaconda, a base about 50 miles north of Baghdad. “And I thought, ‘Well I got that nasty letter saying they were going to put me in jail if I don’t show up.”‘

Anthony Breaux, 24, from La Place, La., said he had a feeling that eventually he would be recalled to service after hearing of so many other soldiers who were pulled from IRR status. Breaux, who left active duty in September 2002, said he knew it was part of the bargain when he joined the army.

“Well, I signed up. I signed the papers. So you know what? I got to do what I got to do,” Breaux said, before getting ready for a reconnaissance patrol around Camp Anaconda.

Loren Thompson, a defense analyst with the Arlington, Va.-based Lexington Institute, said part of the reason that the military has called up so many people who were on reserve status is that certain skill sets such as military police or civil affairs were concentrated in the reserves after the Cold War ended.

But he said the sheer numbers of IRR soldiers being mobilized also are a sign that the military doesn’t have enough people to fight this war, now in its fourth year.

“It seems clear in retrospect that the active-duty force wasn’t big enough to sustain a ‘long war’ against global terrorism, and also lacked the proper mix of skills to wage that war with maximum effectiveness,” Thompson said.

That thought is echoed by many of the IRR soldiers. Mulligan said the military’s reliance on IRR soldiers shows how “desperate” the services are for troops.

“Maybe it says something for maybe the way the military is treating the people that are over here, because they’re just not wanting to stay on,” said Mulligan.

Some of the IRR soldiers, such as Carlson, still will have time on their military contracts when they return from this deployment, meaning they could possibly be called back another time. But others will end their IRR status around the same time their deployment in Iraq ends next spring or will have so little time left that they would not be deployed again.

Spc. Mark Wiles, 27, of Phoenix, said his 61/2 years of active duty and the time he’ll have served on this deployment mean that his reserve status will be over when the unit gets home. The only way that the military could keep him is if they extended the unit’s stay in Iraq.

“Those of us who are IRR are seriously hoping they don’t do that,” Wiles said.