IF THE RACIAL POLITICS of the 2010s has a definitive chronicler, it is Ta-Nehisi Coates, whose magisterial 2014 Atlantic essay “The Case for Reparations” forced Americans to reckon with slavery, Jim Crow, and redlining. Since the essay’s publication—which eventually prompted a congressional hearing on the subject this year, at which Coates testified—the 44-year-old has won a National Book Award for his 2015 book, Between the World and Me, and was awarded a MacArthur “genius” grant. More recently, he’s been writing fiction: He scripted a run of Marvel’s Black Panther comic and published his celebrated first novel, The Water Dancer, which concerns an enslaved man gifted with supernatural powers in antebellum Virginia. Coates’s expansive imagination and incisive, historically grounded writing about Barack Obama, Donald Trump, and cultural figures like Kanye West…