The US–Korea military alliance, forged in the crucible of the Cold War, has long been regarded as one of the most resilient and indispensable pillars of East Asian security. But embedded within his rhetoric was a powerful subtext: a call for South Korea to build a strong, self-reliant military capable of standing on its own in a volatile region. Unlike its northern adversary, South Korea lacks nuclear weapons and has depended for generations on the credibility of US extended deterrence. If South Korea were dragged into a military confrontation with Beijing, the peninsula could once again become the frontline of a much larger regional conflict. The beginning of the end of the US–Korea military alliance is not about rupture or betrayal.