WASHINGTON — A year ago, Marine Capt. M. Matthew Phelps might have been relieved of his command in San Diego if the military found out he was gay. On Tuesday, he stood in a packed Pentagon auditorium and openly discussed his sexuality.

"I happen to be gay, but more importantly, I'm a Marine," Phelps said as heads nodded and murmurs of approval swept through the standing-room-only crowd of several hundred people.