This article is an attempt to develop a theory of peace education through an examination of the Fukushima Daiichi nuclear disaster. It examines why Japan did not avoid this terrible nuclear disaster. This is an educational issue, because one of the major impacts of Fukushima's catastrophe is that it indicates the failure of peace education. In order to reestablish a theory of peace education, the concept of domestic tranquility is discussed. This article questions whether the Japanese public order is consistent with democratic principles. Jane Roland Martin's examination of the concept of domestic tranquility is shown relevant. Martin's language analysis helps to distinguish whether or not Japanese domestic tranquility under nuclear crisis is democratic. I propose that post-Fukushima disaster peace education should be reformed as consistent with two democratic principles: acceptance of the diversity of peace and continuous negotiation among these different narratives.