Summer of Our Discontent is out now from Knopf. Photo-Illustration: Mark Harris; Photos: Getty Images, Beacon Press. On February 18, 1965, students at Cambridge University assembled for a debate between James Baldwin and William F. Buckley Jr. on the topic of racism in America. Before a rapt audience, Baldwin spoke of not only the stolen labor of slaves that had enriched the Southern economy but also the daily humiliations of being Black — “the policeman, the taxi drivers, the waiters, the landlady, the landlord, the banks, the insurance companies, the millions of details 24 hours of every day which spell...