From Peripheral Frontier to Strategic Node to Structural Variable Taiwan, AUKUS and the Defense of the Indo-Pacific Order

Abstract Taiwan and the Structural Transformation of the Indo-Pacific Order This thesis investigates the progressive transformation of Taiwan's strategic significance within the Indo-Pacific order, tracing its trajectory from a marginal maritime frontier under imperial Chinese rule to what this work terms a "structural variable" in contemporary great-power competition. The central argument holds that Taiwan's geopolitical relevance is not intrinsic to its geography, but a historically constructed condition shaped by successive structural reconfigurations: Japanese colonial integration, Cold War institutionalization within the U.S.-led containment order, and the post-unipolar regionalization driven by China's military rise under Xi Jinping. Moving beyond the bilateral U.S.-China framing, the thesis examines how Taiwan's strategic weight has diffused across the regional order, with particular focus on Japan and Australia as secondary but increasingly critical actors. Japan's geographic exposure has driven a fundamental reassessment of its security posture; Australia, historically distant from cross-strait dynamics, has undergone a parallel recalibration culminating in AUKUS. The partnership is analyzed not as a direct defensive commitment to Taiwan, but as an institutional expression of the regionalization of the Taiwan question — a structural adaptation to a threat environment in which China's A2/AD capabilities have eroded U.S. deterrence credibility. The thesis ultimately argues that Taiwan has ceased to function as a frozen residue of the Chinese civil war and has become instead a structural variable of the Indo-Pacific order: a node around which the credibility of American deterrence, the security calculations of regional allies, and the stability of the existing international system increasingly converge — and increasingly depend.