Abstract
This paper examines the transformation of U.S. Indo-Pacific defense strategy under Donald J. Trump’s second presidency, emphasizing how the continuation and intensification of “America First” policies reshape the regional security architecture. Building upon the strategic shift initiated in Trump’s first term—from counterterrorism to great power competition—the study identifies China as the central strategic competitor and explores Washington’s multidimensional response across economic, technological, military, and alliance domains. The analysis traces how measures such as reciprocal tariff regimes, export controls on critical technologies, and defense initiatives like the Pacific Deterrence Initiative (PDI) reinforce deterrence and operational resilience against China’s military expansion. It further assesses the interplay between U.S. internal defense restructuring—through Distributed Maritime Operations, Multi-Domain Operations, and Agile Combat Employment—and strengthened alliance networks including Japan, South Korea, the Philippines, Australia, and Taiwan. Each regional actor is adapting its defense posture: Japan institutionalizes joint operational command, South Korea expands to an Indo-Pacific role, the Philippines revives base cooperation, Australia implements a denial strategy under AUKUS, and Taiwan enhances asymmetric deterrence. The study concludes that this evolving U.S.-led “networked deterrence architecture” marks a structural reordering of the Indo-Pacific, where nationalist bilateralism and democratic coalition-building coexist amid intensifying great power rivalry.