NEW YORK - Madison Square Garden sits girdled in "sally ports," a system of modern-day castle doors designed to foil truck bombs or other terrorist attacks.
On the eve of the Republican National Convention, federal and local officials boast of fielding the nation's largest show of force to secure any political gathering, including 10,000 New York City police officers and thousands more from the Secret Service and 64 other agencies.
Then there's the softer side of mayhem prevention: New York Mayor Michael R. Bloomberg's offer of restaurant and museum discounts to any among the incoming hordes of demonstrators willing to don "peaceful political activist" buttons.
But no amount of planning or cajoling can eliminate the questions hovering over New York, which is intent on keeping its customary cool in the face of uncertainty and anxiety.
Will the surge of protesters - including an anti-war march today past the convention site - rattle a city where many still haven't fully recovered from the Sept. 11 attacks?
And, more ominously, might terrorists return to the home of Ground Zero?
The intersection of those two concerns is foremost in the minds of many protesters, a broad array of groups as varied as anarchists and Mothers Against Bush, who marched across the Brooklyn Bridge on Friday with small children in tow.
Other protesters - thousands of them, many on bicycles - closed down several streets in Manhattan's East Village on Friday evening in an early large confrontation with police. As traffic ground to a halt in the bustling lower Manhattan neighborhood, where protests are part of the historic fabric, police appeared to treat the demonstrators delicately as they arrested them and placed them in a blue and white police bus.
As midnight approached, hundreds of police officers stood watch as crowds gathered.
"The world is watching us now," a group of onlookers chanted as others held signs bearing derogatory messages meant for the visiting Republican convention delegates.
The convention is an opportunity for New Yorkers "to take back their streets" from the Republicans and reject the Bush administration's policies, particularly after the terrorist attacks, said David Graeber, a spokesman for the A31 Action Coalition, which advocates nonviolent civil disobedience.
"This war in Iraq has made us all less secure," Graeber said, "and especially New Yorkers, because we're here in the bull's-eye of any future attack."
Some terrorism experts suggest that an attack on New York this week is unlikely, given how heavily fortified the city is, with the remaining 27,000 police officers protecting the rest of the city. The U.S. Open tennis championship begins tomorrow, and the Yankees and Mets games are in town.
"Look at al-Qaida's operation over the years. They like soft targets," said Randall Larsen, founder and chief executive of Homeland Security Associates, a Virginia consulting firm.
If it occurs, such an attack would probably be somewhere other than New York, Larsen added, because the terrorists could "get the same psychological impact by hitting the soft target at the right time."
A terrorist strike isn't the only violence feared this week. Many of the activists who have converged on New York fear that images of demonstrators clashing with police will play into the hands of Republicans.
During an open house for protest groups at St. Mark's Church last week, Jessi Arrington worked at a table advocating a decidedly low-key protest against the Iraq war. Called "Light Up the Sky," it urges people to gather across the city from dusk to dawn tomorrow "with candles, flashlights and plastic wands to silently express our sorrow over all the innocent deaths the war has caused."
"This is a way to express dissent without giving [Republicans] what they want," Arrington said, "the scenes of violence to be rebroadcast over and over again to influence those 2 or 3 percent of people who are still undecided."
The first big test of how police and protesters will behave is likely to come at noon today, when the anti-war coalition United for Peace and Justice plans to lead more than 200,000 people up Seventh Avenue and past the convention site.
They had hoped to then converge on Central Park, but Bloomberg refused to budge, contending that such a large crowd would ruin the grass on the Great Lawn, which was restored several years ago. After months of back-and-forth negotiations, organizers announced a police-approved route that will instead turn back downtown and finish at Union Square.
But United for Peace and Justice is a coalition of hundreds of individual groups, so there's nothing to keep the folks from, say, Terre Haute Stop War on Iraq or the Ruckus Society from heading for the park. The group noted as much when it announced its new route.
Asking supporters "not to organize breakaway marches" to the park, the group pleaded in a statement: "To those who wish both to march with us and to assert their right to assemble in Central Park on Sunday, we ask that you follow our march to the end, disperse peacefully at Union Square, and then make your own way to the Great Lawn."
Whatever happens, New York's police insist that they will not overreact. "We're going to prepare for any contingency," said Inspector Michael Coan, an NYPD spokesman. "And we're going to exercise good judgment and a common-sense approach."
Some groups have purposefully spurned the city's official protest permits. The A31 Action Coalition, for instance, has set Tuesday as the Day of Direct Action, coyly suggesting dozens of "locations for action," including the offices of such representatives of the military-industrial complex as Lockheed Martin, GOP delegate hotels and Bloomberg's home.
The Chicago Tribune is a Tribune Publishing newspaper.