David Friedman / NBC News Oumama Kabli, center, celebrates becoming a U.S. citizen during a naturalization ceremony on April 15 at the Library of Congress in Washington, D.C. Kabli, 19, is a private in the Army National Guard and entitled to become a citizen without the normal five-year residency requirement because of her military service.

This story is part of NBC News’ series “Immigration Nation,” an in-depth examination of immigration in America.

A wartime edict to entice immigrants to join the military in exchange for rapid naturalization has created 83,000 new American citizens. But one critic worries the initiative will become permanent — or perhaps even expand — essentially outsourcing more U.S. combat jobs and, he argues, injecting the armed forces with an increased security risk.

Launched via a 2002 executive order by President George W. Bush, the program lets green-card holders who enlist in the U.S. armed services bypass the typical five-year residency rule and apply immediately for citizenship at no fee. More than 10 percent of such naturalization ceremonies have taken place in 28 countries abroad, including 3,412 in Iraq, 2,102 in Japan and 1,134 in South Korea, according to U.S. Citizenship and Immigration Services, or USCIS, which administers the process.

In 2008, a one-year pilot program – called Military Accessions Vital to National Interest (MAVNI) – was approved. The program allowed the armed services to tap non-citizens without green cards — here on temporary visas or under refugee or asylum status — to naturalize to help bolster branch needs for specific language or medical skills. “The initial pilot program ran through December 31, 2009 and had a cap of 1,000 total recruits for all services,” Pentagon spokesman Lt. Cmdr. Nate Christensen told NBC News.

Last May, the program was brought back for an additional two years with a cap of 1,500, he said. Thus far, the Army has enlisted fewer than 600 soldiers, and no other branch has used the MAVNI authority.

“I feel like I’m living the American dream,” said Oumama Kabli, 19, who was naturalized April 15 during a ceremony at the Library of Congress in Washington, D.C.

Born to a Moroccan mother and raised in Canada, she moved with her mom to Virginia to finish high school and attend college. She’s now an Army National Guard private with plans to enter officer training. (Only U.S. citizens are eligible to become commissioned officers). A Muslim, Kabli believes “it’s an advantage for the Army to have people familiar with the religion or the culture” when troops deploy to predominantly Muslim nations.

'Citizenship meant everything'

Just as her Moroccan stepfather did in 2004.

“I actually left (Army) basic training, got my naturalization on Friday and was on the plane to Iraq on Saturday morning,” said Youssef Mandour, 31, who worked as a translator, reaching the rank of sergeant. He pulled a second tour of Iraq from 2009 to 2011, working on reconstruction efforts for the State Department.

“Citizenship meant everything. At that point, I was ready to die for my new country,” added Mandour, who arrived from Morocco on a tourist visa at age 17. Today, he owns a defense contracting company in Virginia. “I’m so proud of Oumama. By making her a U.S. citizen it’s going to create that diversity we’re missing in Iraq and Afghanistan. She will be more received by (Muslim) nations than the normal officers from, say, Alabama.”

Source: U.S. Citizenship and Immigration Services

Ending the current naturalization-through-service program would require a new White House executive order, said USCIS spokesman Daniel Cosgrove. All military candidates must pass brief civics and English language tests and then undergo background checks for serious criminal histories or possible affiliations with terrorist groups.

“The thing I’m concerned about is not what’s happening now in the military but what could happen if the Pentagon and politicians get too enamored of this idea of non-citizens joining the military,” said Mark Krikorian, executive director of the Center for Immigration Studies, a nonpartisan research organization in Washington, D.C., that advocates tighter immigration policies.

The White House won’t rescind the 11-year program, Krikorian predicts, even after the scheduled 2014 pullout of American troops from Afghanistan, and “it will become a de facto feature of military life.” Further, that immigrant pipeline may be enlarged, he added, “if we open up the officer corps to non-citizens.” In that scenario, he foresees many foreign students joining in order to stay in America permanently.

Slideshow: Your newest fellow Americans John Moore / Getty Images Nearly 700,000 immigrants take the step to U.S. citizenship each year. Meet some of those who have just become part of that select group: Americans. Launch slideshow

'All bad things can start small'

But if global events transpire that compel the branches to rapidly expand their ranks, he also can imagine a scenario in which the military perhaps further loosens the rules, allowing foreigners abroad to enlist and serve by dangling citizenship as “their compensation.”

"You have the real possibility of soldiering becoming a job that Americans won’t do — just like the Roman empire, not to get too melodramatic about it," Krikorian said. "That’s not something that’s around the corner. But all bad things can start small."

An armed force composed of a far higher share of noncitizens also could boost the security risks for all soldiers and intelligence officers, he added.

"Being an immigrant or from a recent-immigrant family just adds an additional layer of concern, as we saw with Maj. Nidal (Hasan), the Fort Hood shooter, or Army veteran Ali Mohamed, one of the leaders of the (1998) African embassy bomb attacks," Krikorian said. "The vulnerability to blackmail also increases if the target has family members outside the U.S. who can be threatened — drug cartels have used this tactic to compromise Customs or Immigration agents with relatives in Mexico.

"For the ordinary soldier, my main concern is still numbers. The question is: How many noncitizens are being recruited by the military, and are there any restrictions” on how many green-card holders and temporary visa holders can the armed forces approach in a given year?

'The U.S. is my new home'

Pentagon spokesman Maj. Erik Brine responded: “We have no restrictions or limits on the recruitment of foreign nationals who are lawfully admitted for permanent residence.”

Today, about 35,000 formerly foreign troops span active-duty, National Guard and reserve units, according to the Department of Defense. (That equates to 1.3 percent of the total force strength). The policy was first used during the Revolutionary War when the federal government allowed noncitizens to enlist and it was revived during the War of 1812, the Civil War and both World Wars.

New U.S. citizens serve the modern branches in a variety of roles, including health care, languages, aviation, logistics and infantry. Christensen, the Pentagon's spokesman, said they "will continue to play a vital role in the U.S. Military."

David Friedman / NBC News Oumama Kabli, right, celebrates with her mother, Sanaa Mandour, after becoming a U.S. citizen during a naturalization ceremony on Monday, April 15, at the Library of Congress in Washington, D.C.

“I am excited that I get to be part of a nation that I’m serving,” said Oumama Kabli. “I’ll always be a Canadian at heart. But the U.S. is my new home, my new adoptive country. It has taken me under its wing. This is where I’m going to live my life.”

“She got to see the process I went through. I’ve told her, ‘I used to be like you but I joined the service,’” added Mandour. “It’s like the iron that shines you up. She wants to help people. I told her that’s the best way that you can help people.”

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