North Korea twice conducted ballistic missile tests close to Japan in 1998 and 2006. While Japan responded with non-coercive condemnations to demonstrate its disapproval in 1998, it imposed unilateral economic sanctions in 2006, marking the first instance in post-World War II of applying a substantial coercion to punish a neighbouring state. The research asks why Japanese policy toward the North shifted for a seemingly identical type of provocation. The dissertation seeks contextual explanations by using inductive process-tracing, a type of ‘middle approach’ between historical narratives and parsimonious theories. It is applied to highlight the underlying mechanism through which public discursive changes concerning national security and North Korea during this eight-year period influenced the subsequent policy shift in 2006. The dissertation concludes that the unilateral sanctions were not necessarily a calculated strategic response to punish the missile launch (or North Korean nuclear programs) per se, but were a direct consequence of a deeper shift in societal discourse taking place beforehand. During the eight-year period, there had been other visible provocations and shocks originating from the North, especially the sensational revelation in 2002 of past North Korean abductions of Japanese citizens. These highly-publicized incidents facilitated the Japanese public to be increasingly conscious about Japan’s security weaknesses and re-evaluate its historical relations with its neighbour, leading to a hardened domestic environment in which the new idea of pressuring the North became a feasible option even before 2006. These North Korean provocations and the resulting societal security discourse, along with concurrent structural changes in the Japanese government and mass media which made them both highly susceptible to discursive currents among citizens, mutually interacted to produce the policy result when the opportunity arose. The research, however, also challenges the popular view that the sanctions are the first example of the wholesale transformation of Japan’s post-war ‘pacifist’ security principles. It argues that the confined means (economic) by which the sanctions were imposed reflects the highly nuanced discourse, which endorses Japan’s legitimate right to specifically punish the North for the harms done, but that the societal momentum is not equally supportive of the more controversial areas concerning military usage and the current constitution.

North Korea twice conducted ballistic missile tests close to Japan in 1998 and 2006. While Japan responded with non-coercive condemnations to demonstrate its disapproval in 1998, it imposed unilateral economic sanctions in 2006, marking the first instance in post-World War II of applying a substantial coercion to punish a neighbouring state. The research asks why Japanese policy toward the North shifted for a seemingly identical type of provocation. The dissertation seeks contextual explanations by using inductive process-tracing, a type of ‘middle approach’ between historical narratives and parsimonious theories. It is applied to highlight the underlying mechanism through which public discursive changes concerning national security and North Korea during this eight-year period influenced the subsequent policy shift in 2006. The dissertation concludes that the unilateral sanctions were not necessarily a calculated strategic response to punish the missile launch (or North Korean nuclear programs) per se, but were a direct consequence of a deeper shift in societal discourse taking place beforehand. During the eight-year period, there had been other visible provocations and shocks originating from the North, especially the sensational revelation in 2002 of past North Korean abductions of Japanese citizens. These highly-publicized incidents facilitated the Japanese public to be increasingly conscious about Japan’s security weaknesses and re-evaluate its historical relations with its neighbour, leading to a hardened domestic environment in which the new idea of pressuring the North became a feasible option even before 2006. These North Korean provocations and the resulting societal security discourse, along with concurrent structural changes in the Japanese government and mass media which made them both highly susceptible to discursive currents among citizens, mutually interacted to produce the policy result when the opportunity arose. The research, however, also challenges the popular view that the sanctions are the first example of the wholesale transformation of Japan’s post-war ‘pacifist’ security principles. It argues that the confined means (economic) by which the sanctions were imposed reflects the highly nuanced discourse, which endorses Japan’s legitimate right to specifically punish the North for the harms done, but that the societal momentum is not equally supportive of the more controversial areas concerning military usage and the current constitution.