The growing literature on ontological security has generated important insights about the behaviour of individuals, groups, and states in international politics. It has thereby greatly contributed to the discipline of International Relations (IR), especially to IR theory and the sub-field of Security Studies. By focusing on the ‘security of the self’ and the consequences of feelings of anxiety, Ontological Security Theory (OST) challenges the primacy of physical security-seeking and gives us a way of accounting for the psychological underpinnings of security-seeking in IR. Yet, in spite of its contribution to rethinking some of the fundamental tenets of the discipline, Ontological Security Studies (OSS) retains assumptions characteristic of IR as a whole, and is itself characterised by certain biases and ambiguities. Motivated by a desire to continue OSS’ critical engagement with IR, to sharpen OST as an analytical tool, and to advance our empirical understanding of state behaviour and the world, this dissertation adopts a conceptual lens to analyse and rethink two of OST’s key concepts: ‘self’ and ‘anxiety’. Specifically, it traces the usage of ‘self’ and ‘anxiety’ through the current OSS scholarship, and compares it with some of the literature’s precursors in sociology, phenomenology, and psychological existentialism. This makes it possible to recover lost meanings, on the basis of which the OST framework is rethought and applied to current IR issues in East Asia.

In adopting a strategy of recovering lost meanings, the five self-contained articles in this dissertation do not seek to return to a ‘purer’ reading of ontological security or to imply that these readings are more ‘correct’. Rather, the articles treat past usages of ‘self’ and ‘anxiety’ as sources of inspiration, which can complement current OSS and propel it forward by highlighting and problematizing underlying assumptions. They aspire to make us see and understand actor behaviour differently. In pursuing this aim, the articles provide an in-depth engagement with OSS and make three interrelated arguments. First, the ontological security-seeking ‘self’ is an embodied self, which suggests not only that we need to consider the bodies of states and other actors in IR, but also that physical and ontological security-seeking are closely intertwined and not easily distinguished. Second, though often equated, the concepts of ‘self’ and ‘identity’ are analytically distinct, from which it follows that ontological security is not reducible to matters of identity. Instead, ontological security is better understood, and provides greater analytical purchase, as consisting of multiple dimensions, which together create and reaffirm a sense of personhood. Third, while feelings of anxiety are ubiquitous, not all anxieties are the same, which is why it is useful to recover the existentialist distinction between normal and neurotic anxiety. Doing so allows us to account for different kinds of behavioural responses without falling into the trap of equating all anxiety with a lack of ontological security.

Ultimately, this dissertation reveals the crucial importance of concepts for shaping our analyses and imagination, develops the recovery of meaning as a key strategy to rethink concepts and theories, points to the important role of sovereignty in the ontological security-seeking of states, and advances OST by critically engaging with and rethinking two of its key concepts.