The Republicans’ bizarro conclave in Milwaukee, for all the lip service it gave to “unity,” was cloaked in extremist rhetoric and the shadow of violence: Only two days before it began, an assassin tried and failed to kill the GOP nominee, Donald Trump. Next up, the Democrats. The party’s leaders, now in considerable disarray, will gather 90 miles south, in Chicago, for their national convention. And it’s not lost on historians that Grant Park, stretched along the shores of Lake Michigan in the city’s downtown Loop, has been a kind of American omphalos: a venue for celebration, surely, but also a portal to the belly of the American beast.

Borne out of the ashes of the Great Fire of 1871, the 312-acre park was established three decades later, and its elegant promenades and groomed lawns soon became a people’s playground, the site of both the Art Institute and Field Museum. During World War I, the traveling US Government War Exposition held a highly attended spectacle there, with a display illustrating trench warfare, medical treatments, and new technologies.

In my lifetime, two other gatherings in Grant Park—one not too unlike trench warfare—altered the trajectory of American history. The battle, of course, occurred in late August 1968, when the Democrats held their presidential nominating convention at Chicago’s now defunct International Amphitheatre. At the height of the Vietnam War, the left was livid that incumbent president Lyndon Johnson had anointed a hawkish VP, Hubert Humphrey, as his successor. Running against Humphrey was Senator Eugene McCarthy of Minnesota, a vocal war critic, whose stance was echoed by some 10,000 anti-war activists who had swept into town to make their voices heard.

The Yippies of the Youth International Party were there, along with the Black Panthers, the Students for a Democratic Society, the National Mobilization Committee to End the War in Vietnam, and others. Some had applied for permits to hold protests in the city’s parks, and all but one had been denied. As delegates arrived in Chicago, the city’s taxi drivers and electrical workers were on strike, hobbling transportation and communication. Some 12,000 police officers were on the streets, working 12-hour shifts, and Chicago’s hard-line mayor Richard J. Daley had called in the Illinois National Guard.

On the eve of the convention, roughly 1,000 protesters descended on Lincoln Park on the city’s North Side. Later, the police swarmed in, beating those who wouldn’t leave the area. The New York Times reported that guardsmen had received instructions to address “threats of tumult, riot, or mob disorder.” As the convention got underway, tensions rose and violence flared in the streets and on the convention floor. Dan Rather of CBS News was assaulted on air by private security as he attempted to interview a delegate and warned that the Windy City was at a proverbial boiling point. On assignment for Esquire counterculture writer William S. Burroughs was shocked by the police brutality. “The Life-Time photographer is laid out on bench medics washing his eyes out,” he wrote. “Outside the cops prowl about like aroused tomcats.”

The only permit Daley granted was for those who assembled in Grant Park. As 15,000 came to hear anti-war leaders, including David Dellinger, Jerry Rubin, and Tom Hayden, police formed a cordon around the park and armed guardsmen took up positions on the Field Museum’s roof. The same day, convention delegates rejected McCarthy’s anti-war plank and nominated Humphrey after demonstrators erupted in outrage. When a hippie climbed a Grant Park flagpole, cops responded with mace, tear gas, and nightsticks, clubbing activists unconscious. Activist Rennie Davis was one of those beaten, and the bloody rag used to clean his wounds was later hoisted up the flagpole. Protesters and press alike were pummeled as if for sport.

The havoc was captured by TV news crews. First NBC then the other networks interrupted their convention coverage to air footage from “the Battle of Michigan Avenue.” The scene was a disaster for Democrats. From the convention, Connecticut senator Abraham Ribicoff denounced Daley’s “Gestapo” tactics. The mayor, in the hall, shouted at Ribicoff, calling him “a fucking kike.” Out on the street, the tear gas was so thick, the clouds wafted into Humphrey’s 29th-floor suite at the Conrad Hilton.

More than 90 million Americans watched Chicago unravel on TV, among them a gleeful Richard Nixon, who had accepted the Republican nomination just a few weeks before in Miami Beach. He immediately seized on a law-and-order message; days later, he motorcaded through town like a reincarnated Douglas MacArthur, come to liberate the city.

On Election Day, Nixon trounced Humphrey. A few months later, an investigative panel blamed the Chicago chaos on “unrestrained and indiscriminate police violence,” made all the more shocking because it was “inflicted upon persons who had broken no law, disobeyed no order, made no threat.” The Medical Committee for Human Rights reported that 425 peace activists were treated at its facilities.

The college-age demonstrators were in part concerned about being drafted to fight in a war they were against. That’s why Phil Ochs’s defiant anti-war ballad “I Ain’t Marching Anymore” was sung with vehemence by the peaceniks. That August, he’d gone to Chicago at the McCarthy campaign’s request to perform anti-war concerts. The experience rocked the troubadour to his core. As he would later observe, Chicago was “just a total absolute police state…top to bottom.” The following year, disillusioned by American politics, he released the album Rehearsals for Retirement with his own imagined tombstone on the cover. Its inscription: Phil Ochs (American); Born: El Paso, Texas, 1940; Died: Chicago, Illinois, 1968. (In fact, Ochs hung himself in his sister’s New York City apartment on April 9, 1976.) Pope John Paul II arrived in white vestments in 1979 and held a papal Mass in Grant Park, perhaps exorcising some of the site’s violent stigma. Chicago’s vast Roman Catholic community had shown up in droves the night before to hear the pontiff pray, “May God uplift humanity in this great city.”

Flash forward to November 4, 2008, Election Day. Barack Obama of Illinois, a local community organizer turned US senator, was poised to win the presidency. Projecting the audacious optimism that had fueled his unprecedented campaign, Obama had returned home to Chicago to vote. He watched the returns at the Hyatt Regency. When he was projected the winner, at 11 p.m., the Secret Service whisked the president-elect to Grant Park, where 240,000 supporters waited.

In his 2020 memoir, A Promised Land, Obama recalled the experience with awe: “I can see in my mind even now some of the faces looking up as I walked onstage, men and women and children of every race, some wealthy, some poor, some famous and some not, some smiling ecstatically, others openly weeping.” Jesse Jackson, who himself had run for the presidency, was in the crowd. “I was crying,” he would recount. “I thought about the moment. The movement. Those who could not make it to Chicago. The people who had made that night possible.”

On that mild November evening, the promise of American democracy finally seemed at hand. “A change is gonna come,” Obama said, evoking Chicago native Sam Cooke’s 1964 Civil Rights hymnal. That evening restored a bit of America’s soul.

Recently, I returned to Grant Park, with its skateboarders and couples holding hands. I just wandered. At the time, the nation’s campuses were roiling with unrest over the plight of Palestinians in Gaza. A 1968 redux seemed highly possible. I remembered how poet Allen Ginsberg, in a bid for calm amid the mayhem back then, had sat lotus-style, offering a melodious “om.”

From August 19–22, the Democrats will hold their convention at the United Center. Fear of pro-Palestinian protesters flocking to Chicago may have faded—and there may be more chaos inside the arena than out on the streets—but in the aftermath of the recent assassination attempt, security will be amped up. One major difference between ’68 and ’24 is that the Secret Service and law enforcement—as they have at every other such convention since Daley’s day—will prevent demonstrators from congregating near the site. It’s unclear whether city permits will be issued for people to protest solely in Grant Park. But rest assured: If there are any flare-ups against police, any mistreated American flags, Donald Trump will instantly seize the law-and-order mantra, as Nixon did, in his efforts to reclaim the White House come November.

The whole world will be watching.