The Marines were at the gay rights center at the invitation of Toby Jenkins, the center’s executive director, who said he saw no better way to celebrate the end of “don’t ask, don’t tell” in a conservative state that strongly supports the military.

“If we’ve been fighting for 15 years for the right to be in the military, we said, ‘Let’s just ask military recruiters if they’d be available,’ ” he said. “But no one was prepared for that question. It was like I was talking to people like they were deer in the headlights.”

The Marines did in fact think that Mr. Jenkins’s invitation might be a hoax, so they checked him out and talked to their superiors, who talked to their superiors. Then they took a deep breath and decided to go. As the day wore on, the Marines said the bust in recruiting had been made up for in media exposure and public relations. Sergeant Henry and his public affairs officer, Capt. Abraham Sipe, gave interviews at the center with five local television stations, three print reporters and one correspondent for National Public Radio. In between, gay rights supporters stopped by to shake their hands…

By 5 p.m. the Marines had packed up their booth and chin-up bar and headed out, with plans to come back later to attend a panel discussion. It was all uncharted territory. As Sergeant Henry had said the day before of the new world the Marines now inhabit, “At first it’s going to be kind of shock and awe.”

But like a good Marine, he was with the program: “My take is, if they can make it through our boot camp, which is the toughest boot camp in the world, then they ought to have the opportunity to wear the uniform.”