I live in San Francisco just west of Twin Peaks, the hills that hold back the ocean fog and guarantee a remarkably un-San Franciscan number of sunny days in the gay part of town to the east.

And Friday, when I got on the streetcar to go to the Prop 8 protest at the Civic Center, I had to stand all the way downtown, because what looked like every student at San Francisco State was on their way to the protest, too.

I’m sure some of them were queer – my gaydar pinged a few times. But there were lots of boy-girl couples, young people of every ethnicity, computer geeks and pierced-eyebrow performance arts majors, straight boys clinging to their girlfriends’ hands, giggling young people texting back and forth with friends at the other end of the train, girls in rhinestone-studded flip-flops debating earnestly if they should get off at the Church St. or Van Ness stations to pick up the march.

When I got downtown, it was much the same, only on a much larger scale. The age range had increased, from babies in their parents arms to veterans of the ACT-UP days of the ’80s, from those of us who remember Harvey Milk and watched police cars burning at City Hall, to those earnest young people hungry for their defining moment of protest in the cause of equal rights for all of us.

Maybe I should have expected it. I’d experienced something like it on election day, standing on a street corner with a group of “No on 8″ volunteers holding campaign signs, getting thumbs up and honked horns and cheers of support from grizzled old Chinese men and hip young black teenaged boys, soccer moms and ten-year-olds, bus and truck drivers, elderly women walking their dogs. But the crushing loss of the day after had wiped out that high, and I’d forgotten.

“Gay, straight, black, white: marriage is a civil right,” they chanted. The hundreds of people trapped in rush hour traffic while we streamed by opened their windows and pounded the sides of their cars, whooping in support. People stood in open sunroofs and climbed onto the hoods of their cars, waving signs they’d written on pieces of paper: “Stop the Hate – Repeal Prop 8.”

There were no arrests, and the entire counter-protest consisted of two guys with “Protect Marriage” signs that I read about in the morning paper. No one I know even saw them. And despite the complaints of imminent bloodthirsty persecution from a vengeance-fearing religious right, the only threat I heard didn’t involve any form of violence or destruction.

“We’re liberals, sweetie,” said one man marching next to me. “We’re not going to burn their churches. We’re just going to tax ‘em.” He waved to a group of people on the sidewalk, with hand-lettered signs saying “Tax the church,” a chant lustily taken up by the passing marchers.

The march had begun at the Civic Center, near the steps of City Hall that had gone up in flames and violence in the aftermath of Dan White’s manslaughter conviction for the assassination of Harvey Milk and Mayor George Moscone in 1978. It had poured down Market St., the main east-west artery of the city, and tied up with traffic and public transit at the busiest time of day. As we turned into the Castro, though, things slowed down, the narrower neighborhood streets forcing us to crush closer together.

The streets now were lined not with restaurants and office buildings but homes, and in many of their windows were whole families, kids included, waving “No on 8″ campaign signs, and cheering. Two men pulled a wagon with two children, wrapped in a blanket, down the sidewalk, and one little girl stood on her porch, “No on 8″ stickers pasted to each cheek, her smiling moms next to her.

I stopped at the drugstore at the corner of 18th and Castro to buy a new memory card for my camera, since I’d left my spare one at home. The guy who helped me was around my age, and he nodded out the door to the noisy, endless crowd in the street. “Those aren’t all gay people, are they?”

I shook my head. “They’re really not. Kind of amazing. And nice.”

He smiled, and it was radiant. “It never used to be that way.”

“No,” I said. “It never did.”

I don’t know what will happen to Prop 8 as it faces challenges in the courts. I don’t know what’s inside the hearts and minds of those who think this is fair or just, or those who think somehow our families are a threat to theirs. I don’t know what will happen in all the other states with these mean-spirited amendments, or what exact path we’ll have to follow to win our equality under the law.

But I do know that we’re very far from alone in this fight, and that we have one ally that our opponents don’t: we have the young people of this country, and that means we have the future.