Donald Trump’s foreign policy decisions are contributing to increasing uncertainty regarding the United States’ commitment to providing security in East Asia. This has initiated a wave of re-evaluation among regional powers concerning their strategic positions. Doubts are surfacing about the long-standing “US security umbrella,” traditionally relied upon by allies. Nations are now compelled to reassess their defense strategies and explore alternative arrangements. This shift signifies a potential realignment of the East Asian geopolitical order. The evolving situation suggests a move toward greater self-reliance and potentially increased regional competition as countries adjust to the changing landscape. Experts anticipate further strategic adjustments as the region navigates this new era of uncertainty.