With world leaders set to arrive in Chicago this weekend for a long-planned summit of the North Atlantic Treaty Organization, reinvigorated Occupy protesters plan to take to the streets in large numbers, hoping to disrupt tight security with marches and impromptu street theater in neighborhoods throughout the city.

While delegates and military attaches hunker down for talks in the cavernous McCormick Place convention center — in virtual lockdown for the duration of the two-day event Sunday and Monday — Occupiers will be outside the protective barriers engaging in actions that could block traffic and bring clashes with police.

Along with a rally held in Daley Plaza on Friday, they plan to march to Mayor Rahm Emanuel’s home Saturday. On Sunday, they will walk from Grant Park to the fringes of the convention center, where several veterans of the wars in Iraq and Afghanistan plan to give back some of their medals.

Representatives from Occupy Chicago — which has been coordinating the logistics for the week — say they’re hoping to seize the moment as global attention turns to the president’s home town.

Busloads of protesters began arriving Thursday from cities across the country. As many as 10,000 people could attend Sunday’s march for peace and economic equality, organizers say.

“With such a huge event like NATO, it’s the perfect forum to get our message out there,” said David Oloroso, 23, a retail clerk who has been with Occupy Chicago since it formed in September.

Thirteen protesters have been arrested in smaller actions leading up to Sunday’s big march, police said, including eight who were among a crowd that stormed President Obama’s reelection headquarters Monday.

Separately, 11 protesters were arrested after a raid on a house in the Bridgeport neighborhood Wednesday night, and their lawyers issued a news release disputing accounts that they had materials to make molotov cocktails, saying police had confiscated “brewing equipment.” The Associated Press reported Saturday that three of them had been charged with conspiracy to commit terrorism, possession of an explosive or incendiary device and providing material support and that the men faced a bond hearing later in the day.

Six others were released Friday without charge, the AP said.

Large swaths of downtown will be closed to parking and traffic throughout the summit, and a no-fly-zone will be enforced overhead. High-profile delegates will be whisked through the streets in motorcades and dine on Great Lakes whitefish and Colorado lamb Sunday at a dinner hosted by Emanuel (D) at the Field Museum. (A plan to serve a French dessert called “The Bomb” was apparently nixed.)

Meanwhile, protesters will be taking public transit and eating rice and beans or veggie tacos.

Initially, the NATO summit and the meeting of the Group of Eight were supposed to be in Chicago. But in March, White House officials who feared a security meltdown moved the G-8 to the quieter confines of Camp David.

The Occupy movement declared victory and decided to continue the Chicago protest, taking up such wide-ranging concerns as the environment and the closure of local health clinics.

Chicago police — who have an unhappy history with large-scale protests — say they’re ready, equipping officers with $1 million in new riot gear, pepper spray and, in some cases, crowd-control training. The city also has “sound cannons,” which emit an ear-splitting chirping noise.

Police Superintendent Garry McCarthy said in an interview Wednesday that he thinks such tools will not be needed, although he doesn’t rule out “extracting” law breakers from crowds, if necessary. “The bottom line is . . . this is going to be a very positive event for the city,” McCarthy said.

Scores of volunteer lawyers from the National Lawyers Guild will be on hand as observers in case there are clashes or further arrests, which — despite police assurances — seems at least possible, given the attendance of black-clad anarchists — the so-called Black Bloc — who scuffled with police during Occupy’s May Day protests on the West Coast.

“We anticipate mass arrests,” said Sarah Gelsomino, a guild lawyer. “We have to be prepared.”

More than 1,000 nurses and hundreds of other protesters marched Friday through the streets of a downtown that seemed largely deserted but for dozens of police officers and hired security guards. Many businesses had been closed in advance of the summit. The nurses from National Nurses United, the country’s largest nurses union, wore green Robin Hood hats and chanted “Tax, tax the rich.” They are calling for a tax on Wall Street transactions they say can bring in billions for jobs, health care and poverty programs.

Linda Carter, a 50-something nurse who works at a VA hospital in Augusta, Ga., said she came because she’s tired of seeing her veteran patients struggle.

“It makes me feel ashamed,” she said. “A country of our resources, we should be able to take care of people.”

On Thursday, dozens of police blocked passageways and closed parts of One Prudential Plaza as a small group of Occupiers gathered in front of the Consulate General of Canada to protest a proposed oil pipeline.

“People are angry. There’s a lot to be angry about in the entire world,” said Alexandria Banks, 19, a Columbia College student. “I don’t think we should be focusing on what is going to earn the industries more money. We should be focused on what’s good for people.”

Obama — who is due to arrive with other world leaders after the conclusion of the G-8 talks — is not popular with the protesters. He got his start as a community organizer not far from where Banks was standing, helping form a tenants’ rights organization at a public housing complex on the South Side. But she and others say they feel the president has lost his way.

“It doesn’t matter who is in office this point, it’s the corporations that are running it,” said Jessica Reznicek, 30, a Des Moines resident who was arrested at Obama headquarters Monday. “Obama did bring hope, but nothing is changing.”

Reznicek turned up Thursday at the Occupy’s “convergence space” — a welcome center set up at a church in the Lakeview neighborhood on the city’s north side. Inside, volunteers set out literature and programs for the week. Protesters played an out-of-tune piano; some took turns trimming their hair into buzz cuts.

A handwritten calendar on the wall listed the events for the week, including classes in nonviolent resistance and how to be a clown. (A group of protesters who call themselves ClownBloq have taken social media by storm with plans to don circus outfits and march to protest the “absurdity” of NATO. )

Backpacks and sleeping rolls were stacked in a corner. Occupiers have found places for 300 people to stay in churches and local homes, but hundreds more will be camping out. Reznicek, who found lodging in a former convent, said such privations are necessary to solidify the movement.

“Sometimes when you live in a world of truth, you feel really isolated,” she said. “You seize any chance you can to connect with other people.”