The more than three years long summit disengagement following the rapid chilling of relations from late 2012, immediately after the heydays of ROK-Japan ;;shuttle diplomacy”, was a puzzling turn of events. Although the initial discord of 2012 could be attributed to several visible events like President Lee’s visit to Dokdo, it is difficult to provide an easy answer as to why such discord continued for such a long time in the form of summit disengagement. There have been troubled relations in the past, but this was the first time summitries were foregone for such a long time. This paper seeks to explain this anomalous summit disengagement between the ROK and Japan during the years 2012~2015. Based on the understanding that Realist and Liberal security/utility maximizing rational choice models prescribe closer cooperation and not disengagement between the ROK and Japan, I have employed the Constructivist approach to analyze the 2012~2015 summit disengagement by employing the concepts of national identity and historical memory, and their functions in the ROK-Japan relational dyad. As a result, from examining various statements of the two countries’ heads of state and their foreign policy conceptions, and how the eventual November 2015 summitry and December 2015 announcement on mutual steps for resolving the issue of comfort women came to be, it was possible to identify frictions between the Park administration’s national identity of regional moderator and the Abe administration’s national identity of resurgent Japan. Specifically, the frictions arose between the Park administration’s pursuits of trustpolitik that conceptualized Japan’s trustworthiness on its succession of ;;correct understanding of history”, and the Abe administration’s passive reactions on issues regarding history due to their controversial nature, the issues’ negative effects to the pursuit of Japan’s pride and honor, and the relatively small presence of the ROK in the administration’s foreign policy conception. Present in this friction were divergent historical memories that conditioned the Park administration’s pursuit of Japan’s ;;correct understanding of history”, and the Abe administration’s pursuit of Japan’s pride and controversies in its domestic politics like those regarding history education. Similar friction could also be found in the issue of comfort women between the ROK and Japan.