Historian Walter Johnson, author of "The Broken Heart of America: St. Louis and the Violent History of the United States," joins local civil rights icon, Percy Green, founder of ACTION and the man who climbed the arch--to talk about a range of issues pertinent to Johnson's new book including racism, labor organizing and civil rights activism. The interview was conducted with two hosts from the Informal History editorial board, Umar Lee, veteran podcaster and St. Louis activist and Miranda Rectenwald, historian and archivist at Washington University.