This article provides a critical analysis of the representations of collective memory of the atomic bombing of Hiroshima and Nagasaki at the end of the Asia-Pacific theatre of World War II. The discussion of the “subject debate” over the inscription of the Cenotaph for the A-bomb Victims, politics over the construction of the Hiroshima Peace Memorial Park and the preservation of the A-bomb Dome transpired the memory mechanisms at work with regard to the US responsibility for the A-bomb, the Japanese aggressive war leading up to the A-bomb, Japan's colonial rule of Korea, and denationalization and universalization of the A-bomb experience in Japan as a result. The article analyzes the chronology of the “only A-bombed nation” notion in the post-WWII Japanese “peace” discourses and concludes that it was a process to reconstruct Japanese national victimhood as a reaction to the “discovery” of the Korean A-bomb victims and the DPRK nuclear program. The article overall challenges the notion of “peace” and “pacifism” in post-WWII Japan that revolve around the experience of the atomic bombing.