A recent espionage case involving active-duty military personnel has renewed concerns about internal security vulnerabilities in Taiwan. While the investigation is ongoing, the case highlights how modern infiltration rarely relies on a single actor, instead operating through overlapping roles spanning military access, media influence and information networks. Often described as a “fifth column,” these internal risks raise difficult questions for a democratic society under sustained external pressure. How can Taiwan deter infiltration without undermining civil liberties? In this episode, we examine the evolving nature of fifth-column risks, proposed national security law amendments, gray-zone pressure from China, and how Taiwan can strengthen democratic resilience while preserving openness and rule of law.
