Takashi Uemura, a former journalist, is under attack for his reporting on “comfort women.”Credit...Ko Sasaki for The New York Times SAPPORO, Japan — Takashi Uemura was 33 when he wrote the article that would make his career. Then an investigative reporter for The Asahi Shimbun, Japan’s second-largest newspaper, he examined whether the Imperial Army had forced women to work in military brothels dur