“No place else in the United States is going to let Black people take over the streets for four hours long,” Cotton once said about second lines and New Orleans. “It’s just not gonna happen.” If only for a few hours, Black people at a second line parade could feel free—free to express themselves however they wished, regardless of the white world’s constraints. “The blues came from slavery,” said Gregg Stafford, a prominent New Orleans brass band leader and trumpet player. “Jazz came from freedom.”

But demons of death, never far away in New Orleans, haunted that Mother’s Day second line. Ambulance workers counted 20 people wounded and told Detective Hart to expect three, possibly four, fatalities. Measured by total casualties, it was the biggest mass shooting in the modern history of New Orleans, long one of the US’s deadliest cities, with a murder rate eight times higher than the national per capita average.

Surgeons questioned whether Cotton would live through the night; the bullet that hit her pierced her right hip and tore diagonally upward, shredding vital organs before lodging beneath the left side of her rib cage. Later that afternoon, the surgeons emerged from the operating room to inform her loved ones that it didn’t look good. She’d been shot in what hospital workers nicknamed “the soul hole,” because wounds there were usually fatal.

Nevertheless, Cotton held on long enough to deliver a message that stunned people in New Orleans.

A surveillance video had surfaced the day after the shooting that offered a bird’s-eye view of the attack. It showed a Black man in a white T-shirt with his back against the wall of a house, watching as the parade crowd passed from left to right. Suddenly the man pulled a handgun from his pocket, took four strides into the crowd, and began firing at point-blank range. As bodies fell and fled, the man continued firing. After emptying his weapon, he ran off, out of camera range.

TV networks around the world began airing the video. In the glare of such publicity, the authorities soon arrested two suspects: Akein Scott and Shawn Scott, two African American brothers aged 19 and 23. Each was charged with 20 counts of attempted murder: one for each of the 19 gunshot victims and one for a woman grotesquely injured when she was trampled by the fleeing crowd.

In what police labeled “a miracle,” neither Cotton nor any of the other Mother’s Day shooting victims perished immediately. “We had 20 [sic] people shot at that parade, and not one of them dies?” said Detective Rob Hurst, Hart’s partner at the scene. “If that’s not a miracle, you tell me what is.”

Hovering near death, Cotton somehow dictated a statement from the intensive care unit that a close friend delivered to a hastily called New Orleans City Council hearing. “Do you know what it takes to be so disconnected in your heart that you walk out into a gathering of hundreds of people who look just like you and begin firing?” she asked. Alluding to the bleak circumstances facing many young Black men in New Orleans—parents absent or impoverished, abysmal schools, rampant gang and police violence, few job possibilities beyond menial labor or drug dealing—she said, “These young men have been separated from us by so much trauma.”

Cotton was fully aware of the violence Black people had long endured from trigger-happy police and white vigilantes: Her activism over the past eight years had focused on reforming the notoriously corrupt and violent New Orleans Police Department, a mission embraced by Obama’s Department of Justice, which had placed the NOPD under a federal consent decree four months before the Mother’s Day shooting. But the evils of systemic racism were much broader than police brutality, she believed, their reach more insidious and pervasive.

To Cotton, Black lives mattered even if a Black person had done something reprehensible, like shooting into a peaceful crowd, because, she later told me, “racism can kill Black people even when a Black finger pulls the trigger.” The gunman seen firing into the crowd in the Mother’s Day video “clearly made horrible choices that have ruined his life,” she continued. “But he didn’t do that in a vacuum. This city and this country created that vacuum.”

Two months after the Mother’s Day shooting, the Black Lives Matter movement sprang to life as killings of unarmed Black people seemed to become a recurring feature of American life. Or, more precisely, as such killings became more widely recognized because, like the Mother’s Day shooting, they were captured on video.

Then, the nation’s first Black president was succeeded by Donald Trump, who had risen to political prominence by playing a bizarre variation of the race card—repeatedly suggesting, without evidence, that Obama had not been born in the United States, which meant he was occupying the highest office in the land illegally.

That an unabashed racist could be elected president 150 years after the first Civil War was proof positive that the blood of slavery still pulsed through the American body politic. “If we had done the work that we should have done…to combat our history of racial inequality, no one could win national office after demonizing people who’re Mexican or Muslim,” Bryan Stevenson, a civil rights lawyer who established the National Memorial for Peace and Justice to honor America’s lynching victims, told The Guardian. “We would be in a place where we would find that unacceptable.”

Implanted long before the birth of the nation, the twin evils of racism and slavery exposed the contradiction between America’s lofty ideals—“We hold these truths to be self-evident, that all men are created equal”—and the undeniable reality that white people built the country by enslaving and brutalizing millions of African Americans and slaughtering and stealing the land of countless Native Americans.

The United States has never resolved this contradiction, despite rivers of blood shed over it during the Civil War and since. Schoolchildren are taught that the North’s victory in the Civil War ended slavery, but that is misleading. True, to own other human beings was no longer legal. But formerly enslaved people were provided no recompense, leaving them little choice but to continue working, now as sharecroppers or indentured factory workers, for the very people who had exploited them before the war. In 1864, as the South’s military defeat grew near, William J. Minor, a Louisiana planter, told a fellow Confederate that he hoped the South could rejoin the Union after the war with “things as they were, but perhaps under some other name than slavery”—which is pretty much what happened.

Cotton believed that until America, especially white America, honestly faces what race and slavery have done, and still do, to the country, America will not be free of its original sin. Like an infected, untended wound, the dilemma will keep bubbling to the surface, manifesting in everything from a Mother’s Day shooting in New Orleans, to the continuing murders of Black people by police and vigilantes, to the presidential election—and now, in 2024, possible reelection—of a white supremacist whose fellow neo-Confederates openly endorse waging a second civil war to “make America great again.”

When Cotton and I met face-to-face for the first time, a few months after the shooting, I told her that the event was a book crying out to be written, and I asked whether she would consider writing it after she recovered from her injuries.

She asked me to call her Deb, thanked me for the suggestion, but made it clear she wanted no part of it. It was bad enough to get shot, she explained; she didn’t want to keep reliving the whole ghastly experience by writing a book about it.

Deb did agree, however, that somebody should write a book about it. And that somebody, she said, should be me. An activist through and through, she saw the shooting as a teachable moment that could impart lessons about the ways racism has shaped life in the United States since the days of slavery.

A signature skill of good organizers is the ability to persuade other people to do things that need doing. Deb pointed out that I had written numerous books, witnessed the shooting at close range, and even been shot myself. Fixing her gaze on me, she declared, “Mark, I think you’re called to write this book.” Her use of the term called signaled that she, like me, had grown up in the church, where it was common to hear a person say they felt “called” to make this or that major life decision—called by God, the Holy Spirit, or Deb’s favorite term, the Most High.

My being white didn’t seem to bother Deb. She rejected the view—one that soon became common on the political left in the US—that only Black people were permitted to talk about race. To the contrary, she, like many African American activists and intellectuals over the years, believed that it was white people who most needed to talk with one another about race—and not only race but also slavery, the original sin at the bottom of today’s injustices and pathologies.

“Black people have been talking about it for 400 years, honey,” she told me. “It’s white people who aren’t talking about it.” Besides, she added, white people could be heard by other white people in ways that Black people simply would not be. “White people listen to white people more than they will listen to Black people,” she said. “That’s just a fact.”

With the 2024 elections now fast approaching, the question of how much white Americans will talk about race and slavery—and how such talk might influence how they vote in November—could hardly be more urgent. A good starter question for such conversations was posed in an article the Black writer Chauncey DeVega published in 2016, when Trump ran for president the first time: “What Kind of a White Person Do You Want to Be?”

DeVega, a columnist for Salon, was reacting to the news that a 40-year-old Black man, Terrence Crutcher, had been shot dead by police in Tulsa, Oklahoma. DeVega had vowed to watch no more videos of police murders of Black people, calling them “a type of pornographic violence, a digital-era version of lynching postcards.” He was tired of having to explain how police violence was a legacy of slavery and the nation’s failure to confront that legacy. The reason murderous violence against Black people continued, DeVega argued, was that white America didn’t care enough to stop it.

But white people could make a different choice, he added—in fact, some white people already had. In the 1960s, a young man named Paul Breines was one of numerous white people who joined the Freedom Riders movement of college students who traveled to the South to help Black people claim their right to vote. It was a perilous undertaking: Racists were shooting Black people who dared register to vote and their white allies, too. In a letter to his worried parents, Breines explained that he decided to go south after asking himself the question, “What kind of a white person do I want to be?”

DeVega implored today’s white Americans to ask themselves the same question—and to remember that “silence and inaction in the face of such wrongdoing and bigotry are in fact complicity with them.”

When Trump ran for reelection in 2020, large numbers of white Americans gave the answer DeVega was hoping for. On May 25, a cell-phone video of Derek Chauvin jamming his knee into George Floyd’s neck for more than seven minutes as Floyd gasped “I can’t breathe” left no doubt that a white police officer had just murdered a nonviolent Black man in broad daylight. Floyd’s murder gave rise to the biggest protest movement in US history: An estimated 14 to 26 million people took to the streets in all 50 states.

The protests were led mainly by Black people, but large numbers of white people, especially younger ones, also risked arrest or injury to stand up for justice for Black Americans. This was unprecedented: Never in the 155 years since the end of the Civil War had large numbers of white Americans put their bodies on the line for their Black fellow countrymen. (Yes, some whites did march with civil rights activists in the 1960s, but they were a tiny fraction of the overall white population.)

Echoing Deb’s point about the importance of white people talking to one another about race, Nell Irvin Painter, an African American historian, told The New York Times, “The great stall point after the [1960s] civil rights movement was white people not being able to talk to other white people about whiteness. That has to happen before anything can change. Now, many white people are stepping up and saying, ‘Oh, we’ve got to talk about this.’”

It grieves me to report that Deb did not live long enough to witness those protests in summer 2020 nor the defeat of Trump that November. But now, as Trump tries to return to the White House, I’m reminded once again of why I came to regard her as a prophet.

A Trump victory would be akin to allowing the Confederacy back into power after the Civil War, yet if today’s opinion polls are to be believed, Trump is running neck-and-neck with President Joe Biden. Those same polls, however, as well as actual election results in the 2024 Republican primaries, show that Trump’s base—the MAGA heads who stick with him no matter what—amounts to only one-third of the total US electorate. This means that Trump can only win in November if he also gets millions of non-MAGA heads to vote for him—or at least not to vote for Biden.

It’s that latter category of Americans, the non-MAGA heads whose indifference might enable Trump’s return to power, who Deb had in mind when she warned that afflictions like the Mother’s Day shooting and the rise of Trump will keep happening until more Americans talk honestly about what racism and slavery have done to this country—and do their part to fix it.