Seeking Strategic Autonomy through Regional Trade Agreements: The Path of Institutional Hedging for Middle Powers under the RCEP

In the context of escalating US–China strategic competition, how middle powers in the Indo-Pacific utilize multilateral regional agreements to implement hedging strategies in pursuit of strategic autonomy has become a key topic in the field of international relations. This paper combines neoclassical realism and liberal institutionalism to construct an integrated analytical framework. Using the signing of the Regional Comprehensive Economic Partnership (RCEP) agreement as a quasi-natural experiment and employing a difference-in-differences (DID) model, it systematically examines the impact and transmission mechanisms of a large-scale regional trade agreement on the institutional hedging and strategic autonomy of middle powers. The study finds that the signing of RCEP can significantly promote member states to implement institutional hedging, thereby effectively enhancing their level of strategic autonomy. Mechanism tests find that US–China competition, democratic regimes, and institutional quality significantly and positively moderate the promotional effect of the RCEP agreement on the strategic autonomy of member states. Heterogeneity analysis reveals that the RCEP agreement primarily enhances the institutional hedging efficacy and strategic autonomy level of high-income countries, countries without territorial disputes with China, and countries with low growth rates in their secondary industry. Meanwhile, for countries with territorial disputes, RCEP serves as a crucial institutional buffer to mitigate asymmetric security pressures. Finally, the study corroborates these findings through a discussion of the typical case of Vietnam.