Sinéad O’Connor explained the point of her career in her 2021 memoir: “Everyone wants a pop star. See? But I am a protest singer.”

And her protests were epic. After O’Connor’s death on Wednesday at age 56, there were many recollections of her 1992 appearance on Saturday Night Live, when, in a carefully plotted effort to highlight child abuse in the Catholic Church, she performed Bob Marley’s “War,” urged people to “fight the real enemy” and tore up a photo of Pope John Paul II.

The ensuing backlash upended O’Connor’s career, but she was unrepentant. She had written in her 1991 letter to the Grammys—in which, at the peak of her fame, she withdrew from the awards in objection to the “false and destructive materialistic values” of the recording industry—that “as artists I believe our function is to express the feelings of the human race—to always speak the truth and never keep it hidden even though we are operating in a world which does not like the sound of the truth.”

O’Connor spoke many truths before and after the Saturday Night Live appearance, which shocked the world at a time when child abuse within the church was still largely neglected. She advocated for the unification of her native Ireland, for the rights of Palestinians, for peace when the United States was preparing for attacks on Iraq, for women’s rights in Ireland and abroad, for trans youth, for an end to human rights abuses globally, and for an economic order in which poverty was banished. She took risks, and she wondered why other artists did not. “Thousands of children are starving to death every day…children are being beaten up because of problems in society…children are being sexually abused and emotionally abused, people are living in the streets,” she explained in that 1991 letter. “It’s not enough any more to just sit in you[r] chair and say, ‘Yeah, it’s terrible.’ Musicians are in a position to help heal this sickness, but I’d say 90% of the artists in the music business fail in that responsibility.”

O’Connor took responsibility, raising issues years—even decades—before others who had her level of prominence began to address them. Such was the case with what many argue was her greatest song, “Black Boys on Mopeds.” A cry against the killing of Black teenagers and young men by police officers, the song was recorded more than 30 years before the murder of George Floyd inspired millions to take to the streets in Black Lives Matter protests against police violence. Written in the late 1980s, the song was released on O’Connor’s internationally acclaimed 1990 album I Do Not Want What I Haven’t Got—which, despite her protests, was nominated for four Grammy Awards in 1991 and took top honors for Best Alternative Music Performance.

“Black Boys on Mopeds” was an inspired protest song that began with an instantly memorably blunt denunciation of the hypocrisy of British Prime Minister Margaret Thatcher, who had objected to the Chinese government’s violent crushing of the Tiananmen Square protests while pointedly failing to respond to police violence and systemic racism within the United Kingdom:

Margaret Thatcher on TV Shocked by the deaths that took place in Beijing It seems strange that she should be offended The same orders are given by her I’ve said this before now You said I was childish and you’ll say it now Remember what I told you If they hated me they will hate you England’s not the mythical land of Madame George and roses It’s the home of police who kill black boys on mopeds…

Thatcher inspired many of the finest protest songs in modern history, including the English Beat’s “Stand Down Margaret,” Morrissey’s “Margaret on the Guillotine,” and Elvis Costello’s “Tramp Down the Dirt.” Yet, O’Connor’s “Black Boys on Mopeds”—with its stark observation, “These are dangerous days / To say what you feel is to dig your own grave”—was characterized by a rage that was at once personal and universal.

Irish-born and raised, O’Connor had moved to London as her career soared. She was a witness to Thatcher’s many cruelties. But the prime minister’s response to racism in Britain, and especially to the police violence toward Caribbean immigrants, provoked the singer-songwriter, who was well aware of the UK’s long history of oppressing the Irish. Based on an incident that occurred near where she in London, in which a Black teenager named Nicholas Bramble was chased by police—who assumed he had stolen the moped he was riding—and died in a road crash, “Black Boys on Mopeds” delivered a searing critique of racism in the U.K. “This was at a time when there was a terrible scandal in London about Black men going missing in police stations,” recalled O’Connor in her memoir. “It was a time in London also when if a burglar was apprehended, he was reported as a ‘Black burglar’ (or, alternatively, an ‘Irish burglar’). There was a lot of tension created between Londoners on the one hand and the Jamaicans and the Irish on the other.”

O’Connor’s recognition of systemic racism and her determination to call it out was reflected not just in the song but also in her dedication of the album—which would become an international hit, selling 7 million copies—to the family of Colin Roach, a 21-year-old Black Londoner who had died in 1983 from a gunshot wound in the entrance of a police station in the London borough of Hackney. Police claimed Roach had committed suicide, but jarring inconsistencies in the official story led to widespread protests and a 1983 The Special AKA song (“Bright Lights”) with the lyrics: “I got down to London and what did I see? One thousand policemen all over the street, The people were shouting and looking at me, They say ‘the Colin Roach family demand an enquiry.’”

As the years passed, “Black Boys on Mopeds” remained an essential song on O’Connor’s setlist. She became one of the music world’s earliest and most ardent supporters of the emerging Black Lives Matter movement, to which she donated proceeds from a 2020 cover of “Trouble of the World,” a gospel song made famous by Mahalia Jackson. The video for that song portrayed O’Connor marching alone with a placard and wearing a movement shirt. But O’Connor wasn’t alone. Younger artists had begun to cover “Black Boys on Mopeds,” recognizing it as one of the most meaningful protest songs of our time. Shea Rose, who performed a brilliant version, explained that she was drawn to the song by its continuing relevance in an era that saw rising consciousness of police violence following the deaths of Michael Brown in Ferguson, Breonna Taylor in Louisville, George Floyd in Minneapolis, and so many others. As mass protests across the United States raised the cry of “Black Lives Matter,” the song became a staple in live performances by Phoebe Bridgers, Sharon Van Etten, and others.

Asked about the song’s legacy in a 2021 interview with arts writer Geoff Edgers, O’Connor said: “I get very sad when—it’s actually beautiful, though, but when—the song that gets the most, you know, applause from the audience when I first start singing the lines is actually ‘Black Boys on Mopeds.’ It’s more popular, and nothing compares, and that’s gorgeous. But I always am thinking every night, ‘Oh, my God, isn’t it sad that this is still so fucking relevant, you know, after 30 years?’”