World order is never in stasis for too long. And indeed, we seem to be witnessing a historic shift now. The relatively stable decades after World War II saw gains for global democracies, rapid economic growth fueled by globalization, and the birth of the Internet. But they also saw the speeding of global warming, widening inequality, and the scourge of transnational terrorism. The institutions and agreements that have grounded the modern international order are showing signs of weakness, while illiberal sentiment gathers strength across the West. Nationalism is having a moment. Europe is having an identity crisis. And China is challenging the dominance of the United States. How did we get here? What’s next?