Marian Fontana's husband was a Brooklyn firefighter who was killed on September 11, 2001. Afterwards, she started an organization, fighting to keep her husband's fire station open, and to help victims' families.
Host Ira Glass talks to Stephen Dubner, co-author of Freakonomics, about one of the men in his book, a guy named Stetson Kennedy. In the 1940s, Kennedy, a Southerner, infiltrated the Ku Klux Klan.