This article explores the link between collective memory and state behaviour in international relations. In that regard, it develops a new concept entitled ‘temporal security’. Building on the existing ontological security literature, it extends a temporal understanding to its underlying identity concept. Countries are now assumed to be temporal-security seekers vis-a-vis a ‘significant historical other’ from their past. Decision makers thus enter into a self-reflective conversation with their country’s ‘collective memory’ when choosing courses of action. Contrasted with existing physical-security and ontological security explanations for state behaviour, the explanatory potential of the temporal-security approach is in a second step illustrated by the empirical case of West Germany and Austria, two former Nazi perpetrator states, and their respective assignments of support during conflict in the Middle East. Through a comparative, qualitative discourse analysis of historical documents during the Six-Day War of 1967 and the Yom Kippur War and oil crisis of 1973, the empirical study finds that West Germany and Austria adopted different courses of action in their international politics, because they looked to Nazi Germany as their significant historical other.