Cpl. Joseph J. Brown almost gave his life for a country that wasn't his.

In the deadly Baghdad slum of Sadr City, on Aug. 16, 2004, his Army unit came under attack. Several comrades were out in the open, with insurgents pressing toward them. Brown, a tank driver, grabbed the .50-caliber machine gun on the tank and raked the attackers.

"I knew I was going to die," he recalls. But instead, "I took them down, the bad guys."

The citation on the Army Commendation Medal he earned that day says his courageous actions "led to the safe evacuation of his crew despite numerous IED's."

He brought home something else from that day -- wounds from an explosion during the firefight, including spinal injuries, nerve damage to his left leg and post-traumatic stress disorder. In boot camp, he could run two miles in 11 minutes, he says, but now walking too far hurts his leg.

Five months after Brown was wounded, Iraqis cast ballots in their first democratic election in half a century. Back home in the United States, Brown could not vote. He was not a citizen.

An immigrant from Liberia, a legal resident of Woodbridge for six years, Brown had as his only regret the fact that the Army considered him disabled, so he could not get back in the fight.

"My service in the Army was going to be infinite," the 21-year-old veteran says.

Now he's embarking on a different American future.

Your country is worth dying for, isn't it? How about your country's controversial effort to bail out another country?

During wartime with a volunteer military, most born-and-raised Americans can remain utterly cocooned from any sacrifice. Immigrants are playing a small but striking role. The presence of about 37,000 noncitizens on active duty and in the National Guard and the Reserves points up the quandary of what anyone owes to his country.

In 2002, President Bush ordered that noncitizens in the military as of Sept. 11, 2001, be immediately eligible to apply for citizenship, rather than having to wait the usual three years. Since then, nearly 25,000 have been naturalized, according to Citizenship and Immigration Services. Citizenship ceremonies take place even in the war zones of Iraq and Afghanistan. On Friday -- Veterans Day -- 110 sailors and Marines were naturalized aboard the USS Midway, the floating museum in San Diego Harbor.

Noncitizens enlist for some of the same reasons Americans do -- patriotism, adventure, money for school, job training. For Brown, serving was a way to say thank you to his second homeland.

The young, wounded veteran speaks the language of patriotic idealism. These days, it can sometimes sound tired, overused, cheapened by self-interest or self-righteousness. But not when it bursts forth so unself-consciously, from someone so young. Maybe it makes a difference that Brown speaks it with a foreign accent. Maybe this soldier can remind Americans of something they never had to think twice about.

"I think everyone should understand that the country is never going to be free without you helping," he says. "It's teamwork."

He does not agree with those who doubt the war. He cannot imagine the United States could commit an error as large as starting a war without good reason.

"I believe America always kept their word," Brown says. "If I were going to die, I believe I was going to die for the right reason, for a country that always kept their word."

He grew up in Brewerville, Liberia. His father was an accountant, his mother a homemaker.

The Browns suffered during the invasion and war with Charles Taylor's rebel forces in the 1990s. Once at a checkpoint, one of Brown's older sisters was raped. His mother was beaten. When the boy tried to go to the women's side, a rebel with a bayonet jabbed him near the collarbone.

Brown's mother came to America first, then arranged for the rest of the family to be admitted in 1999, Brown said.

"It was terrible for us," he says, recounting his story before dawn one recent morning at Walter Reed Army Medical Center. He continues the tale later in the morning at Veterans Affairs headquarters downtown, where he volunteers.

Tall and slim in a coat and tie, Brown speaks haltingly of life in Africa but turns exuberant when the scene shifts to America. He remembers being surprised upon landing at New York's Kennedy International Airport with nothing but the clothes on his back: He had always pictured America as a kingdom in the sky, not on the ground.

The congregation of Bethel United Methodist Church in Woodbridge adopted the family of 13, renting and furnishing a house and feeding and clothing them for a little more than a year. "They were just fantastic people," says Fred Parish, the pastor.

Brown's father became a security guard at a car dealership; his mother became a home health aide.

Joseph, the second-youngest child, carried a feeling in his heart, a restless sense of indebtedness. He became a cadet with the Prince William Volunteer Fire Department, but that didn't make the feeling go away.

He was beginning his senior year at Woodbridge High School when a jetliner crashed into the Pentagon. "I wanted to quit school at that moment to join the Army and go fight the bad guys," he says. A teacher persuaded him to wait until after graduation. Before long he was driving a tank in the streets of Baghdad.

"I don't regret him joining the Army; he got a lot of experience from it that made him much stronger and braver," says Hietha Brown, Joseph's father, who was once a captain in the Liberian militia.

The work of a tank driver in a combat zone seemed equal to the feeling in the young man's heart.

"People like us coming from disaster to a peaceful land, we should give back," Joseph Brown says. "I didn't have money to give. I gave myself."

As the war continues and potential recruits know they may be sent into combat, the number of noncitizen volunteers has been declining, adding to the military's overall recruiting woes. The annual number fell nearly 20 percent from 2001 to 2004, the Associated Press reported. As of last spring, 142 noncitizens had been killed in action in Iraq and Afghanistan, 8 percent of the total -- a higher proportion than their representation in the military, according to the AP.

Those still signing up sound certain. Eric Jon, 30, of Rockville, who emigrated from China with his parents and sister when he was 14, joined the Army around the same time as Brown. He already had a bachelor's degree in accounting, so it wasn't for tuition money. Instead, Jon's motives sound a lot like Brown's.

"The motherland didn't treat us so well," Jon says one day after sharing a lunch of buffet Chinese with Brown. Jon became a citizen after enlisting but before going to Iraq. He was recently honorably discharged after being wounded. "I got so much benefit from this country. It's part of citizen duties. . . . It's something I felt from the bottom of my heart. I wanted to serve."

Sam Rocha, 25, of Gaithersburg, felt the allure of military culture while still in high school. He talked to recruiters, but his parents were reluctant. He convinced them that the American military was nothing like the Colombian army, especially because of all the education benefits. The family had emigrated when Rocha was 2.

He joined the Army Reserve in 1997 and was assigned to an engineering unit. The Army helped pay for a degree in international business that he has nearly finished. His mother's fears came true when the war started and Rocha's unit was assigned to build bridges during the sweep into Baghdad.

"I told my parents if I died fighting for the U.S., I still wanted to be buried in Colombia," says Rocha, a Colombian citizen who feels a dual loyalty. "I love Colombia. I admire the United States."

Riding in a convoy in the first days of the invasion, Rocha noted the poverty of the country and imagined that toppling the regime would help the common people. Now he's not so sure. "I don't want to talk bad, but I think it's a lot of politics," he says.

While recuperating from his wounds, Brown began volunteering to do computer work at the Department of Veterans Affairs. In January, when he is scheduled to be honorably discharged, that position will become a job. Instead of a career as an American soldier, the Liberian native envisions a future serving American veterans.

Now he is an American, too. In August, he and another wounded soldier recited the oath and became citizens in front of a two-star general. Because of his bad leg, Brown was told he could sit while swearing allegiance to the United States, but he insisted on standing. He leaned on a cane gripped with his left hand while he raised his right hand.

Brown's sergeant had been pressing him to become a citizen, but Brown put it off. He didn't understand why it was necessary. He already felt like an American. He didn't need a piece of paper. However, with his Army service about to end, his sergeant finally convinced him it was a step he should take. "The whole time I was smiling and smiling," Brown says. "I felt like they were making me a citizen twice for the country."

Army Cpl. Joseph Brown became a U.S. citizen a year after he was wounded serving in Baghdad. While recuperating from battle injuries, Brown has been volunteering at the Department of Veterans Affairs.Joseph J. Brown, left, earned an Army Commendation Medal for his actions when his unit was attacked in Baghdad in 2004.