AS SOON AS you stepped on the subway platform to catch the train from Brooklyn to midtown on February 15, you knew things in New York City were different. At 10 a.m. on a Saturday morning, the station was packed with yuppie women in North Face down coats sporting no war on iraq buttons and talking about antiwar groups marching from churches and plazas all over the city. You knew this wouldn’t be some pansy Union-Square-10-person protest. Right then and there, you knew this was some serious business. No self-respecting New Yorker gets out of bed this early on a Saturday morning.

And it was ... serious business.

A caravan of police vehicles speeding down 42nd Street greeted protesters emerging from the Times Square station, on their way to 49th and First — Ground Zero for the International Day Against the War. And from 9 a.m. to 6 p.m., New York resumed a 9/11 feel, with police blockading more than 10 blocks surrounding the protest’s stage site, barely letting even media with legitimate, police-issued press badges through. After five or six check points, most eventually got in, but not without a bit of hassling. New York cops hate protesters, but they really hate journalists.

The police and the blockades and the battle over permits did not keep protesters from coming, though — en masse.

Whatever recent New York antiwar demonstrations lacked in attendance, they more than made up for on February 15. Looking from the stage down First Avenue, all you could see was a sea of people — 30 square blocks of them — standing in the 20-degree weather and carrying signs with slogans such as draft the bush twins and freezing my ass off for peace.

" Everyone I know was trying to get off work for this demonstration, " said Alison Whittington, a waitress and student from Brooklyn. " We’re all poor as shit, and people were giving up their best Saturday shifts just to be here. "

United for Peace and Justice, which organized the rally, did not disappoint the crowd. After a hellish week of first being denied a police permit to march by the city, and then having that denial backed up by a federal-court judge, the group still managed to obtain permission to demonstrate and rally (although not to march). It set up a stage and garnered no fewer than 64 speakers, including Rosie Perez, Susan Sarandon, Danny Glover, the Reverend Al Sharpton, and Harry Belafonte. Although the celebrities said lots of good stuff, the meat of the no-war argument came from Amit Mashiah, a former Israeli soldier representing 500 other soldiers opposing the war.

" It took 12 years of fighting for me to realize two things: a) violence can never solve conflict, and b) peace is not our goal; peace is a way to our goal, " he said. " According to Abraham Lincoln, the best way to neutralize the enemy is to make him your friend. All the oil wells in Iraq are not worth one drop of innocent blood. "

The real coup for United for Peace and Justice, though, came when a little gray-haired guy (clad in a cap and navy-blue pea coat) named Archbishop Desmond Tutu took the stage. The Nobel Peace Prize laureate talked extensively about how demonstrations such as these brought down the Berlin Wall and ended apartheid in South Africa. His speech stopped everything in a transcendent moment.

" God is looking down on you and smiling. God is looking at First, Second, and Third Avenues and saying, ‘Aren’t these people neat,’ " he told the crowd in awe. " Mr. Bush, listen to the voice of the people, for many times, the voice of the people is the voice of God. Vox populi, vox Dei! "

Four hours, millions of frozen toes, thousands of cups of soup, and some serious inspiration later, the rally disbanded into little pockets on various Manhattan corners and things got kind of ugly, as they often can when people come up against New York’s " finest. " The NYPD could have taken a few lessons from the benign Washington, DC, police, who exercised restraint on the National Mall a month ago.

Clad in riot gear, no less, officers charged after relatively friendly protesters exercising their constitutional right to congregate. At 53rd and Third, a group of six students who were conducting a sit-in and chanting, " Bush is on crack, ’cuz this attack is wack! " faced off against a wall of 10 cops sporting helmets and billy clubs, who were ready to take them out should they get more active. Minutes later, aggressive mounted police charged up against a large crowd, pushing it back from a mass arrest of other protesters so no one could witness it — an NYPD-style cover-up. The cry " Fucking pig " was heard often as the horses, with fright in their eyes, took on much smaller, just-as-scared people. Many also wondered aloud who would give such orders — Mayor Michael Bloomberg? The police commissioner? John Ashcroft?

At some point during the horse incidents, small armies of police on scooters headed west as protesters ignored the ban on marching and advanced toward Times Square. Some chaos ensued. Traffic was blocked for another good hour (poor, unsuspecting New Jersey shoppers), and then, rather anticlimactically, everything ended.

By 6 p.m., police captains started telling officers to " go warm up in the van. " " Things have calmed down substantially, thank God, " said one officer, who wouldn’t give his name to a reporter. " Today was a mess. " By 6:30 p.m., cops toting nylon riot-gear briefcases on their way home talked with New Yorkers. Some were in favor of the war, some clearly were not. " We were just doing what was ordered over the radio, " said one. In any case, it was clear that the New York police were unprepared for the size of the crowd.

Earlier in the day, one protester — who worked as an EMT on 9/11 — summed up the attitude of many who work as protectors of the social order: " Most of the people in my profession can’t come up for air to think of alternatives to war for all the security threats, " said Meg Bartlett, who was among the first on call when the Twin Towers collapsed. " We fear another September 11. "

But Whittington, the waitress, does not.

" My mom called when the [homeland-security threat-level] indicator hit orange, but being around these people makes me feel more safe than ever, " the Florida native said. " Just looking around here today makes me think we are headed for peace. "

She could be right. Bush could ignore 20,000 people last spring and 100,000 last fall. He could try to ignore 300,000 a month ago. But, although he declared Tuesday that he won’t be deterred by global protests, he cannot ultimately ignore 500,000 people gathering two blocks from the United Nations building — or the millions of other people who took part in 600 protests around the world last weekend.

Adrian Brune can be reached at ambrune@earthlink.net