Abstract
This contribution argues that transnational inequality (inequality between countries) matters because it affects leaders’ perceptions of fairness and hence their willingness to contribute toward securing global public goods. There has been a significant convergence in per capita national income levels over the past three decades, and this helped to lift billions of people out of income poverty. However, major inequalities in two crucial areas remain and have worsened. Climate iniquities and divergences in preventative and curative health provision, and the effect of a ballooning post-COVID public debt crisis, rest heavily on the minds of leaders in the industrializing world, affecting their responses to multilateralism as a global institutional form. This problematizes the cooperation required to deal with the main geopolitical challenges of our era, namely, the mitigation of and adaptation to climate change, cybersecurity, financial stability and the amelioration of sovereign debt, reliability of global supply chains, development and distribution of preventative and curative medical care, and managing rivalry between the interdependent giants of the world economy.