The story of how Barney Frank became the nation’s first openly gay member of Congress pretty much begins with a double date on New Year’s Eve in Egypt in 1982. Frank traveled with Sen. Thomas R. Carper (D-Del.), who was then a House colleague and not yet married. Carper had met two female flight attendants on the trip to Egypt and set up a double date with Frank. “It was clear that I was not nearly as interested as he was,” Frank said. “So he asked me the next morning whether, why I was not more forthcoming with the friend, and I told him.” He was gay, but not ready to be openly so. Frank (D-Mass.), who is retiring after more than three decades in Congress, is easily the nation’s most prominent gay politician and one who charted a path for others like him.