川普第二任首年交易式外交邏輯下臺灣戰略風險之再評估

A Reassessment of Taiwan’s Strategic Risks Under the Logic of Transactional Diplomacy in the First Year of Trump’s Second Term

本文以川普第二任首年為觀察範圍，探討川普交易式外交語言及其政策邏輯，如何透過制度承諾之鬆動，影響臺灣之戰略風險認知。本文主張，交易式外交不僅是川普外交風格之展現，更是一種使安全承諾條件化與可議價化之外交邏輯，並進一步重塑美－台關係中的制度信任與風險評估架構。研究方法上，本文採質性脈絡分析法，建構由「川普交易式外交邏輯」、「制度承諾穩定性」、「臺灣戰略風險認知」與「避險行動策略」所組成之分析架構，以釐清外交語言、制度承諾與政策回應之間的連動關係。研究發現，當美國對台承諾之可預測性與一致性下降時，臺灣對美國安全支持可信度之疑慮將明顯升高，並促使政策社群採取多邊連結、制度備援以及風險分散等避險作為。理論上則以「交易式模糊外交」概念，補充既有戰略模糊與制度承諾研究，對語言轉向及風險生成機制之解釋不足；於實務上，則建議臺灣建立外交語言預警機制，強化制度韌性與戰略回應能力。

This article takes the first year of Trump’s second term as its period of observation and examines how Trump’s transactional diplomatic rhetoric and policy logic, through the loosening of institutional commitments, has affected Taiwan’s perception of strategic risk. The article argues that transactional diplomacy is not merely an expression of Trump’s diplomatic style, but also a diplomatic logic that renders security commitments conditional and negotiable, thereby further reshaping the structure of institutional trust and risk assessment in U.S.-Taiwan relations. Methodologically, this study adopts a qualitative contextual analysis and constructs an analytical framework composed of“Trump’s transactional diplomatic logic,”“the stability of institutional commitments,”“Taiwan’s strategic risk perception,”and“hedging strategies,”in order to clarify the interrelationship among diplomatic rhetoric, institutional commitment, and policy responses. The findings show that when the predictability and consistency of U.S. commitments to Taiwan decline, Taiwan’s doubts about the credibility of U.S. security support rise significantly, prompting the policy community to adopt hedging measures such as strengthening multilateral linkages, building institutional backups, and diversifying risk. Theoretically, this article proposes the concept of“transactional ambiguity diplomacy”to address the explanatory limitations of existing studies on strategic ambiguity and institutional commitment with respect to linguistic shifts and the mechanisms of risk formation. Practically, it suggests that Taiwan should establish an early-warning mechanism for shifts in diplomatic rhetoric and strengthen its institutional resilience and strategic response capacity.