“Family of Spies”: Christine Kuehn discovers her grandfather’s Nazi past

In 1994 Christine Kuehn received a letter that revealed a family history from which her father had tried to shield her: Christine’s grandfather, Otto, was a Nazi spy who was the only person tried and convicted for the bombing of Pearl Harbor. David Martin talks with Kuehn about her German family conducting World War II-era espionage, a tale she recounts in her new book, “Family of Spies.”