Military service is in Capt. Kamaljit Singh Kalsi's blood.

His father and grandfather were part of India's Air Force. His great-grandfather served in the army in India under the British. So when U.S. Army recruiters talked to him during his first year of medical school, he readily signed up.

But his plans to go on active duty in July are now on hold. An Army policy from the 1980s that regulates the wearing of religious items would mean he would need to shave his beard and remove the turban he wears in accordance with his religious precepts.

Kalsi and another Sikh man with the same concerns, Second Lt. Tejdeep Singh Rattan, are the centerpieces of an advocacy campaign launched by the Sikh Coalition as it tries to persuade the Army to let them serve without sacrificing their articles of faith.

"I'm an American, there's no reason why I can't serve," Kalsi, 32, said.

The Army has a long-standing interest in how its members carry themselves, with policies that ban exotic hair colors, long fingernails or certain colors of lipstick. Army officials declined to comment on the reasoning behind its policy that would force the Sikh men to give up their religious displays. Sikhs who were active-duty military when the policy was adopted were allowed to continue serving without shaving their beards or removing their turbans.

The Pentagon and other military institutions wouldn't comment. The Military Religious Freedom Foundation, an advocacy group, was unfamiliar with the policy's origins.

As the Sikh diaspora has spread across the world, the issue of turbans and beards on Sikhs in uniform has come up in a number of places. In New York City, for example, Sikh traffic officers took successful legal action to force the city to allow them to wear turbans and beards.

The Sikh community is hopeful it will win the policy appeal; in an April 29 letter to the Sikh Coalition, the director of the Army's Human Resources Policy Directorate said senior leadership was aware of the issue and was gathering information to make a decision. Toni Delancey, a spokeswoman for Army personnel, said the appeals are under review.

Sikh Coalition executive director Amardeep Singh said he hopes that not only are Kalsi and Rattan allowed to serve, but that the rule will be changed for all turbaned and bearded Sikhs who would want to enlist.

"Our country's military needs to reflect what America is right now," he said. "It's a diverse country, it's a country that puts forth for the rest of the world the values of liberty, particularly religious liberty."

Allowing Sikhs to serve with beard and turban "will send a very strong message to the rest of the world that we are who we say we are."

The Sikh faith requires adherents to follow certain rules, among them that hair is not to be cut and for men, the wearing of a turban. Both Kalsi, an emergency room doctor, and Rattan, a dental surgeon, say they were following those rules when they were recruited and never had any problems or were told they wouldn't be able to serve with their beards or turbans.

Both said they raised the issue over the years and were reassured, and that it wasn't until the end of last year when they were told they would not be allowed to serve as they were.

The idea that he would have to choose between his country and his faith is hard for Rattan. "I'm offering my life, but I'm not willing to sacrifice my religious beliefs," he said.

Singh said it would be in the military's best interest to lets Sikhs serve. The community has a long tradition of military service, both in India, where most of the faith's adherents are, as well as in the countries where Sikhs have made their homes, like Canada and the United Kingdom.

"As part of our religious heritage, we're taught that we have an obligation to actively serve and protect the communities in which we live," he said.

In Canada, regulations for the armed forces allow Sikhs to keep their turbans and beards, and even determine what colors the different military branches can wear. The Royal Canadian Mounted Police allows turbans as well.

The British Army allows Sikhs to generally keep their articles of faith. For Sikhs who serve as civilian police officers, The British Police Sikh Association is pushing for development of bulletproof turbans. That would allow Sikhs to be part of firearms units, since safety helmets don't fit over them.

Sikhs have a long history with the U.S. military, serving in World Wars I and II, the Korean and Vietnam wars, and in the Persian Gulf.

One of them is Army Col. Gopal Khalsa, who is retiring in November after more than three decades in uniform, all of those with a turban and beard.

His distinctive appearance has required some conversation and explanation at times, but it's never been a problem for him, or gotten in the way of carrying out his duties or wearing his military equipment.

"Of course there's a lot of looks, but once people get to know you and you're doing the job, that falls by the wayside," Khalsa said.

He thought a rule change would be a good idea, saying the presence of Sikh soldiers would be an asset in places where the United States is currently carrying out military operations, like Afghanistan.

"The Army would be gaining successful, useful soldiers," he said.

Kalsi hopes he can be one of those soldiers, and serve his country as generations of his family have done.

"That's what we connect with, that's part of our heritage," he said. "It links us to our past and our present and hopefully the future."