In early December 2019, I sat in a conference room at the federal Centers for Disease Control in Atlanta, listening to its director, Dr. Robert Redfield, answer a question: Is America ready for another major infectious disease like Ebola or the Zika virus? Redfield's response reiterated what most public health experts knew, but coming from him, it was jarring. "It’s not a secret,” he said. “Our nation is not prepared for a flu pandemic.” He was certain such a pandemic would one day arrive, and although he couldn't foresee when, he knew it would be bad: “It’s going to be a huge loss of life.”