The COVID-19 pandemic revealed the complex interplay between national self-interest and global cooperation, showing the need for ethical frameworks that describe the scope of global health obligations. Nationalist perspectives contend that justice is most effectively realised within the nation-state, where governments are accountable to their citizens. Cosmopolitanism, by contrast, challenges the idea that national membership should determine the scope of obligation, arguing that health justice should be grounded in the equal moral worth of all humans. In this presentation, I will argue that global health is shaped by a dynamic interplay between ‘ethical reflection’ during crises and a subsequent ‘ethical amnesia’ that allows for a regression towards national self-interest. Global health, therefore, functions within a reactive cycle where cosmopolitan advancements are contingent upon the failures of nationalist policies, fostering fragile commitments to global health equity and leaving the global community unprepared for future threats. This pattern is evident in the global dilution of cooperative mechanisms once immediate crises wane. To break this cycle, I propose that a country such as New Zealand adopt a 'mutual interest test' for its global health policy. This practical framework is designed to reorient nationalist impulses towards durable cosmopolitan goals by institutionalising mutual interest as the normative baseline for policy. Such a test would move New Zealand beyond rhetoric, ensuring its shared vulnerability is met with durable, shared responsibility and meaningful action.