International relations (IR) scholars are increasingly interested in the role of memory in world politics. In this paper, we examine a key tension in the uptake of memory in IR between its status as a topic studied within IR and its use as an optic through which the basic categories of IR might be rethought. Focusing on the problem of scales of analysis, central within memory studies more broadly, we suggest that while memory poses a challenge to typical scalar arrangements in IR, such as “levels” of analysis, memory is often studied within these very arrangements. We argue that this is significant because questions of scale are at times the central political problem at stake in international memory. We track this tension between topic and optic in studies of memory, national identity, and foreign policy; studies of collective trauma and sovereignty; and studies of conflict and cooperation over memory.