When Nihon Hidankyo, an organization bringing together the victims of the Hiroshima and Nagasaki bombings, won the Nobel Peace Prize last year, all of Japan celebrated.

Politicians also applauded the group — but that did not insulate the government from criticism for not attending a recent United Nations meeting on a nuclear weapons ban, as well as others before it.

Tokyo’s (in)action can be explained by the fact that it holds a dual position: It supports further nuclear disarmament while also being in favor of the United States’ nuclear umbrella, which it relies on for its security. This highlights some of the contradictions in Japanese discourse on the issue, most notably, the absence, in my view, of a significant debate on the key question of nuclear deterrence versus abolition.