Segal was at Stonewall, a gay bar on Christopher Street in Greenwich Village, when New York police raided it on a June night in 1969. Instead of submitting to arrest or fleeing, hundreds of gay men rioted. To many, the uprising marked the beginning of the modern gay-rights movement.
The president referred to Seneca Falls, Selma, and Stonewall in the same phrase, linking an 1848 conference that launched the women's suffrage movement; a 1965 march in which African Americans were beaten by state troopers, shocking the nation; and the gay uprising.
"If I ever doubted it, today I feel fully welcomed into the American family," Segal said, adding that it was not always so for him. "To be arrested, harassed, called 'faggot' . . ."
Gay-rights activists around the nation took Obama's language as recognition that their struggle was legitimate. Historians may eventually see Obama's speech as a tipping point, when gay equality entered the political mainstream, in the same way Lyndon B. Johnson adopted the language of black protest after Selma. "We shall overcome," Johnson told Congress as he announced his intention to introduce a voting-rights law.
"Our journey is not complete until our gay brothers and sisters are treated like everyone else under the law," Obama said.
Mel Heifetz, a Philadelphia real estate developer who donated $1 million last year to a super PAC supporting Obama's election, was ecstatic. "My heart is full of joy for this day and the many more we shall enjoy with Barack in the White House," Heifetz said. "Had it cost double what I gave, I still would have done it gladly."
Now the drama moves to the Supreme Court, where, in March, the justices take up two cases involving state and federal efforts to limit the definition of marriage to heterosexual unions.
Same-sex couples can now marry in nine states and the District of Columbia, but the federal government does not recognize those unions, denying spouses things such as the beneficial tax status given to heterosexual couples, and military or employee benefits. That is at the heart of the challenge to the federal Defense of Marriage Act.
New Jersey has had civil unions for same-sex partners, conferring many of the rights that attend matrimony, since 2007, but gay activists have kept pushing for the same status as heterosexual couples. Last year, the Legislature passed a measure to legalize same-sex marriage, but Gov. Christie vetoed it, saying voters should decide.
Leaders of the Democrat-controlled Legislature are considering trying to override the veto, but have refused to act on a constitutional amendment allowing same-sex marriage that would put the issue before voters.
Pennsylvania's political terrain has been less favorable to gay-rights drives. Since 1996, the state has had a law barring official recognition of same-sex unions. State Sen. Daylin Leach (D., Montgomery) has sponsored a bill to legalize gay marriage, but it has gone nowhere in the Republican-controlled legislature.
That institution does have its first two openly gay lawmakers - Reps. Brian Sims (D., Phila.), elected in November, and Mike Fleck (R., Huntingdon), who revealed last month that he is gay. Bills to ban discrimination against gays in the workplace and in housing, as well as to address hate crimes and bullying, are pending in Harrisburg.
Segal remembers when in 1969, he and his friends wrote in chalk on the walls along Christopher Street: "Tomorrow night - Stonewall!" He said Tuesday, "We didn't realize we were creating a new gay movement. We were just fighting this one injustice."
Contact Thomas Fitzgerald at 215-854-2718, email@example.com, or follow on Twitter @tomfitzgerald. Read his blog, "The Big Tent," at www.philly.com/BigTent.
Inquirer staff writer Joelle Farrell contributed to this article.