Should schools have been closed down? Were lockdowns a mistake? Was masking even effective? Was the economic stimulus too big? These are the questions that have defined the national conversation about Covid in recent months. They have been the subject of congressional hearings led by Republicans, of G.O.P. candidate stump speeches and of too many Twitter debates to count. Katelyn Jetelina is an epidemiologist and the author of the popular newsletter Your Local Epidemiologist. She argues that we’ve entered a new phase of the Covid-19 pandemic: “pandemic revisionism.” In her telling, the revisionist impulse seduces us into swapping cheap talking points for the thorny, difficult decisions we actually faced — and may face again with the next novel virus. So this conversation centers on the myths — and realities — associated with how we remember the pandemic. It explores what the evidence on the effectiveness of masking says, the fact that the United States was locked down for less than two months, the surprising consensus over social-distancing policy among Democratic and Republican governors early in the pandemic, why the tale of Sweden’s controversial approach to the pandemic is misleading, why the American media paid so much more attention to the first 100,000 U.S. Covid deaths than to the next 900,000, why school closures weren’t as wrongheaded a policy as often portrayed in hindsight, whether Donald Trump gets enough credit for Operation Warp Speed and more. This episode was hosted by David Wallace-Wells, a writer at The New York Times Magazine and the author of “The Uninhabitable Earth: Life After Warming.” He also writes a newsletter for New York Times Opinion that explores climate change, technology, the future of the planet and how we live on it.