The crisis unfolding around the Strait of Hormuz is a test of regional stability as well as global leadership. And increasingly, the United States under Donald Trump appears to act less like a stabilizing force and more as an unpredictable variable. At the center of the issue is a simple but dangerous shift in logic. Washington is no longer framing security in terms of shared responsibility, but of relative exposure. Trump’s argument — that countries more dependent on Middle Eastern oil, such as South Korea and Japan, should bear the burden of securing it — may sound pragmatic. In reality, it represents a profound unraveling of alliance principles. This is not strategic clarity. It is strategic abdication dressed up as efficiency. For decades, the global order, particularly in maritime security, has rested on the premise that the United States would act as a guarantor of stability, not because it was especially vulnerable, but because it had the most capacity. That asymmetry was the point. It allowed for coordination and predictability. Now, that logic is being reversed. Capabilit