Recruited in 2009 through the Military Accessions Vital to the National Interest (MAVNI) programme for his language skills, Lamba Wednesday completed basic training keeping his turban and unshorn hair at Fort Jackson outside Columbia.
"I am thrilled to serve with my fellow soldiers and serve the United States of America," said Lamba, who has become a US citizen.
"I humbly believe I was able to excel in all aspects of my training. Most importantly, I was overwhelmed by the support and camaraderie I felt with my fellow soldiers and base leadership. I thank them all and look forward to my service," he added.
Current US Army policy excludes Sikhs who maintain their turban and beard. Sikhs in the US military may maintain their religiously-mandated turban and unshorn hair only if they receive an individual exemption to do so.
Lamba was initially told that his Sikh articles of faith would likely be accommodated.
But, in March 2010, his formal request for a religious accommodation was denied. Lamba appealed the decision, and his appeal was accepted in September 2010.
Contrary to the concerns of some, Lamba was able to meet all the requirements of a soldier during basic training.
He wore a helmet over a small turban during field exercises. During gas mask exercises, he successfully created a seal. He also enjoyed deep bonds with fellow soldiers and his superiors.
In 1981, the Army banned "conspicuous" religious articles of faith, including turbans and unshorn hair, for its service members. The ban was enacted despite a long history of Sikhs serving in the US military with their religious identity intact.
Nevertheless, the past year has seen progress in the campaign to restore Sikh service in the US military.
In March, Captain Tejdeep Singh Rattan, a dentist, became the first Sikh commissioned officer to complete basic training in more than two decades. In September, Captain Kamaljeet Singh Kalsi, a physician, became the second Sikh commissioned officer to complete basic training.
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