As the United States approaches the 250th anniversary of the Declaration of Independence, the country is confronting deep political division and growing questions about its identity. In his new book, “The Greatest Sentence Ever Written,” former CNN Chairman Walter Isaacson joins the show to re-examine the second line of the Declaration and how its ideals continue to shape what it means to be American today. He also reflects on CNN’s founder Ted Turner, who passed away earlier this week. 

Also on today's show: naturalist Sir David Attenborough; author Sherrie Rollins Westie