President Trump directed Defense Secretary Pete Hegseth last week to reduce U.S. participation in joint military exercises with South Korea, a security practice established following the 1954 Mutual Defense Treaty. The president attributed the decision to his relationship with North Korean leader Kim Jong Un, whom he described as "unthreatening and respectful," and noted his dissatisfaction with the long-standing drills. The shift follows South Korea’s decision not to join current U.S. operations against Iran.
The administration is framing these changes under a policy termed "flexible realism." Elbridge Colby, a Defense Department policy adviser currently managing the China-Taiwan portfolio, described the approach as a move toward a "foreign policy of common sense" that prioritizes current strategic needs over "legacy commitments." While Colby previously advocated for shifting resources from Ukraine to Taiwan, he stated during his confirmation hearing that Taiwan is an important U.S. interest but "not an existential one."
During a recent speech in the Philippines, Colby outlined a strategy for the Indo-Pacific that emphasizes partnership over dependency. He indicated the U.S. would seek to achieve strategic objectives with China by downplaying areas of friction. The administration's current list of regional counterparts included Manila, Bangkok, Jakarta, Singapore, Hanoi, and Kuala Lumpur, but the text noted that Taipei was not mentioned in the presentation outside of a general reference to the first island chain in the National Security Strategy.
The transition to "flexible realism" signals a concrete change in how the U.S. manages its defense obligations. For Taiwan, the shift suggests a potential move away from the explicit policy commitments outlined in the 1979 Taiwan Relations Act, which mandates U.S. support for Taiwan’s self-defense. Military contractors and regional allies would notice a change in the "architecture of a true denial defense" as the U.S. moves to accelerate the delivery of "hard combat capabilities" to the theater while simultaneously demanding "greater effort and contribution" from partners. This could result in higher defense spending requirements for allied nations to maintain current security levels.
The knock-on effects include a possible precedent for unilateral concessions in exchange for diplomatic rapport, as seen in the freeze of joint drills following the president's comments on Kim Jong Un. This approach may influence the behavior of other regional actors, including China, Russia, and North Korea, who are currently supporting Iran against U.S. operations. The immediate next step is a scheduled meeting between President Trump and Chinese leader Xi Jinping in Washington next month, which follows the August 24 cancellation of joint Marine drills with South Korea. The deadline for any formal changes to the Taiwan Relations Act or treaty obligations remains subject to congressional action.