In 1973, fans of beloved newsman Walter Cronkite were shocked and appalled when his broadcast of the CBS Evening News was disrupted by a long-haired youth who ran onto the set with a yellow sign that read, "Gays Protest CBS Prejudice."

Mark Segal had arrived.

Son of a cabdriver who grew up in near poverty in South Philadelphia, the then-23-year-old activist made history with his stunt, or "zap," as his guerrilla team, the Gay Raiders, called their political actions.

Minutes later, Cronkite delivered CBS's very first report on a gay protest when he recounted the incident to viewers with his characteristic grace and reserve.

That night, America was exposed the sight of an openly gay man. A rarity.

"Cronkite had 60 million viewers," Segal, 64, said, "and until then many of them had never seen a gay man before. . . . They believed that gays were the green-eyed monster that had been painted for them by their church and the government. I showed them we are their neighbor."

Segal, better known today as the founder and publisher of the Philadelphia Gay News, writes about the incident in his new memoir, And Then I Danced: Traveling the Road to LGBT Equality (OpenLens).

The book is a conversational, nicely constructed combination autobiography and history lesson that recounts Segal's contribution to LGBT activism, from his early days as a member of the Gay Liberation Front in New York to his stewardship of a successful weekly newspaper.

Segal, who had felt like an outsider since early childhood - he was poor, Jewish, and gay - moved to New York to find a sense of community. He was at the bar in the Stonewall Inn in June 1969 when the infamous riot broke out.

"Right after Stonewall, we created the Gay Libration Front, and in that one year, everything changed for us," Segal said during a recent conversation at his apartment atop PGN's Old City offices. With protest came a chance for gays and lesbians to define their own identity.

"Up to that point, we had been defined by the church, by law enforcement, by psychiatry. By everybody but ourselves," said Segal. "And we also created an LGBT community. None had existed up until that point."

Segal moved back home in 1971 to help take care of his ailing mother, but the activism bug had him for life. Fascinated with the power of the media, he decided the next step in the fight for LGBT equality was to take the message to the wider public.

He organized zaps targeting local TV newsman Larry Kane, the Today show, and The Tonight Show with Johnny Carson, getting arrested countless times. (He can't remember how many.)

But Segal also began working with politicians. He explains in the book how the LGBT cause became more viable once it was defined as a civil rights issue and not a question of sex and morality.

And I Danced details how Segal helped establish numerous community projects, including an LGBT community center in the 1970s, and, more recently, a $19.5 million project to build affordable LGBT-friendly housing for seniors.

We learn of Segal's role in crafting an antidiscrimination platform with Pennsylvania Gov. Milton Shapp in the early 1970s, of his many battles with Philadelphia City Council, and of his campaign work for a series of local and national candidates, including Barack Obama, Ed Rendell, and Jim Kenney, who on Tuesday was elected Philadelphia's next mayor.

"Mark Segal's leadership on LGBT rights has been a game-changer, not only for Philadelphia, but for the country," Kenney said by email. "Without his grassroots activism, Philadelphia might never have been recognized by [Human Rights Campaign] for becoming one of the most friendly LGBT cities in the nation."

Segal is at his most impressive when he describes how he has managed not only to befriend but also to persuade leaders previously indifferent or hostile to the LGBT cause. Philadelphia Court of Common Pleas Judge Daniel J. Anders says that as a community organizer and leader, Segal "has spent literally decades converting people into becoming allies of the LGBT community." Those Segal persuaded have included former U.S. Sen. Arlen Specter, Pennsylvania Gov. Tom Corbett, City Councilman Thacher Longstreth, and former Philadelphia Mayors Frank Rizzo and John F. Street.

As City Council president, Street voted against a domestic partnership bill. As mayor, he did an about-face.

"My community despised John Street," Segal said. "But I saw a man with great potential, a man who came from a religious family and had trouble dealing with LGBT issues."

Segal does drop a lot of names in the memoir - Bette Midler, Patti LaBelle, Elton John, Matt Lauer, and Barbara Walters rate plenty of real estate. And he trumpets his accomplishments, but oddly, he never comes across as immodest.

It's rare to see someone so comfortable in his own skin. Lounging in his den, Segal beams, rather like a new mother, as he discusses his brushes with celebs, the role of advocacy journalism, and the importance of history, which he says is lost on the young.

And he's irritated, deeply irritated, by people who ask him whether his work is done.

"They say, 'Oh, we have marriage equality, we have gays in the military, in the White House,' " he said. "Well, is that really all that great when you have statistics [that say] up to 40 percent of homeless people in the United States are LGBT? When you have suicide rates among LGBT youth of 20, even 30 percent?

"There's still a lot of work to be done."