It has been said that if you want to have a friend in Washington, D.C., get a dog. That piece of lore is often wrongly attributed to President Harry S Truman. Truman, like most presidents, did in fact have a close friend and confidante whose advice helped shape national policy. In his new book, First Friends: The Powerful, Unsung, and Unelected People Who Shaped Our Presidents, author Gary Ginsberg delves into the close friendships that two centuries of U.S. presidents relied upon for sound advice amid the climbers and attention seekers who often gravitate to power. Doug McKelway sits down with the author for a closer look.