The world's largest multilateral organization was born out of the global crisis of World War II. Now, as another crisis rocks the world, the United Nations is facing a challenge of its own—to remain relevant in an increasingly nationalistic geopolitical environment. On the eve of the first virtual UN General Assembly, GZERO World host Ian Bremmer spoke to UN Secretary-General António Guterres about pandemic response, climate action, the US/China schism, and more.