While gentrification may seem like a new phenomenon, efforts to combat it have a long history in the United States. WNYC senior editor Matthew Schuerman's new book, “Newcomers: Gentrification and its Discontents,” delves into that history and examines struggles with gentrification in San Francisco, New York City and Chicago from the 1950s to today. Schuerman argues that if we hadn't abandoned certain federal policies in the 1970s, we could have curbed some of today's most stark displacements. We’ll talk with Schuerman about his research of San Francisco’s Mission District and consider ways policymakers can approach the issue of gentrification going forward.