The turning point in Tahara's life came in the summer of 1945. Up until then, he had been taught that Japan was fighting a just war. However, when he returned to school after summer vacation, his teacher started saying the exact opposite: "Japan fought a war of aggression that it should never have fought." This made him question everything he had been taught up to that point. "What was all that I had been taught until now? I can’t trust my teachers, the newspapers, or the radio." This experience became the impetus for him to pursue a career in journalism.[1]
Tahara attended Waseda University and began his career at Iwanami Productions, a documentary film production company.[2] He later moved to TV Tokyo where he made a series of groundbreaking television documentaries,[3] before turning freelance in 1976.
In 1971, he co-directed with Kunio Shimizu the fiction film Lost Lovers (Arakajime Ushinawareta Koibitotachi yo) for Art Theatre Guild, which starred Renji Ishibashi and Kaori Momoi.[4]
"Asa Made Nama Televi! (Live TV Until Morning!)," which began in 1987, is a television program where experts engage in discussions from late at night until morning. Tahara continues to serve as the host of this program to this day.[5]