The Diane Rehm Show

Throughout the 20th century, genocide -- from the Holocaust to the Khmer Rouge regime to the Rwandan massacres -- has prompted American leaders to vow "never again." But in many cases, the U.S. has been accused of intervening too little, too late. Journalist and human rights advocate Samantha Power traces the history of American response to genocide in her new book. Ms. Power is executive director of the Carr Center for Human Rights Policy at Harvard.