Can the United Nations still make peace? In his 2026 Coca-Cola World Lecture at Yale University, historian and former UN official Thant Myint-U examines how the organisation’s role in peacemaking has evolved, from its original vision of enforcing peace to the diplomatic efforts that helped manage conflicts during the decades of decolonisation. Drawing on the experience of his grandfather, former UN Secretary-General U Thant, Myint-U argues that the UN must move beyond its exhausted post-Cold War model and recover its capacity for practical diplomacy and mediation. He calls for a new approach to international cooperation that prioritises peaceful coexistence, protects national sovereignty and gives the UN Secretary-General greater scope to mediate conflicts.