n 2012 George Zimmerman, a neighbourhood-watch volunteer, shot and killed Trayvon Martin, an unarmed 17-year-old boy in Sanford, Florida. His acquittal a year later led Alicia Garza, an activist, to post on Facebook: “Black people. I love you. I love us. Our lives matter, Black Lives Matter.” Soon after, those last three words went viral, after several high-profile killings of African Americans at the hands of police. Black Lives Matter developed into a movement against police violence and racism, with more than 40 chapters in four countries.
Almost as soon as it began, Black Lives Matter met with a backlash. Protest slogans, such as All Lives…