Cori Bush smells tear gas when there isn’t any. Loud noises frighten her, reminders of police brandishing sniper rifles, firing rubber bullets, and revving the engines of armored vehicles. When the video of Minneapolis police officer Derek Chauvin kneeling on George Floyd’s neck began to circulate, Bush’s reaction was instinctual: “Don’t look at it.” She looked anyway. “It’s a reminder that we didn’t finish the work.” For 400 days in 2014 and 2015, protesters gathered in Ferguson, Missouri, to register their outrage over the police killing of unarmed Black teenager Michael Brown.