ALBUQUERQUE N.M. -- During his eight years in the Air Force, Staff Sgt. Justin Lahl grew adept at keeping his sexual orientation a secret -- wincing inwardly when fellow airmen made homophobic wisecracks, nodding with a smile when others would caricature gay people for laughs.
He was painstakingly careful about whom he trusted, telling only his roommate and a few friends that he was gay.
These days, though, Sgt. Lahl, a 26-year-old aircraft mechanic, is not only open about his identity, but he has also become a leader of the Gay-Straight Alliance at Kirtland Air Force Base, a support group for gay and lesbian service members that is the first of its kind in the Air Force.
The new organization at Kirtland, founded with the approval of the base's commander, is one of a handful of similar groups that have been forming at bases around the country since President Barack Obama repealed in 2011 the military's "don't ask, don't tell" policy, which barred openly gay and bisexual people from serving in the military.
Soldiers like Sgt. Lahl represent a new day for the military, in which gay soldiers in increasing numbers are seeking to form official support organizations to help negotiate the unique challenges they face.
"It's been liberating, being able to be myself and not two separate people -- one person at work and one at home," said Sgt. Lahl, who is vice president of the group at Kirtland. "We're not just this nameless, faceless person anymore. We're a presence on the base."
The Kirtland group has about 12 active-duty gay and lesbian members, along with dozens of veterans and civilians, and three straight airmen. In its first year, membership has increased more than fivefold. The base employs about 20,000 people, including more than 3,200 active-duty service members.
While the Kirtland group is thought to be the only one in the Air Force, according to an Air Force spokeswoman, Lt. Col. Laurel Tingley, similar organizations have formed in the Navy.
Last year, Petty Officer 2nd Class Ann Foster started the first chapter of the Gay, Lesbian and Supporting Sailors, or GLASS, at Naval Station Great Lakes in Illinois, the Navy's largest training facility. She said she was moved to form the organization after watching a fellow lesbian sailor struggle to support her spouse and children without the same military benefits given to straight families. The base's commanders threw their support behind the idea, she said, swiftly approving bylaws and a charter.
Within the past few months, chapters have formed on three Navy ships and one additional base, Petty Officer Foster said, and 15 more are in the process of seeking charters.
Petty Officer Foster, 27, attributed the spread of the groups to a new generation of junior enlisted sailors, who grew up accustomed to having openly gay friends and family and for whom the "don't ask, don't tell" policy seemed obsolete. A similar gay-straight support club for midshipmen and military cadets, called Spectrum, has been started at the U.S. Military, Naval and Air Force academies.
"They don't have that innate fear that people who had been in the Navy for longer periods of time and who served under 'don't ask, don't tell' have," she said. "By the time I started GLASS, there were people coming out of boot camp who had never actually served under it."
Nonetheless, Petty Officer Foster noted that there were still Navy commanders who were uneasy about the groups forming under their watch. And at least for now, the organizations appear to be limited, in terms of active-duty service members, to the Navy and the Air Force.
Indeed, the long shadows of "don't ask, don't tell" still hang over some service members.
Even at bases where the groups are operating, navigating the politics of military life can be complicated, said Elise Thomasson, a civilian who was instrumental in helping to start the Kirtland group.
Some commanding officers became noticeably standoffish toward soldiers who had identified themselves as gay, she said.
Ms. Thomasson, whose husband is an officer, described her recent effort to find an Air Force chaplain willing to speak in confidence with a gay airman.
"One guy went, 'I think it's a sin, but I'd be willing to pastor to him.' The second one also thought it was a sin but was willing to do his job. The third one had just come back from a conference on pastoral care for the LGBT community," she said. "If we had known that beforehand, it would have been a lot easier."
Sgt. Lahl, meanwhile, is separating from the Air Force. He plans to join his husband, who is deployed in Iraq, at Scott Air Force Base near Belleville, Ill., in the coming months. Once he settles in, Sgt. Lahl said, he plans to start a support group for gay airmen there too.
"It was hard for Greg and me, that first generation, to come out, but hopefully it will be easier for future generations of airmen and officers," he said. "So they won't have to fear."