Kennedy was unable to enlist in the military to serve in World War II because of a bad back, so he decided to channel his patriotism towards combatting racial injustices in the Jim Crow South. He is best known for infiltrating the Georgia Ku Klux Klan and exposing their secrets on the popular children's radio program "The Adventures of Superman", trivializing their rituals. He also targeted the Columbians, an Atlanta-based neo-Nazi organization. Kennedy said, "There were an awful lot of evils abroad in the world at the time, as there still are, but I couldn't help but feel that racism was perhaps the most evil".