The quarter-century following the end of the Cold War in 1989 was the most peaceful period in history, Michael Mandelbaum argues. He examines the rise of peace in three important parts of the world: In Europe, in East Asia, and in the Middle East. While each region has its particulars, Mandelbaum identifies three broad features conducive to peace that are common to all three regions and beyond: US geopolitical dominance, the growth of economic interdependence, and the spread of democracy. Yet, the peace was lost, mainly due to the policies of three revisionist states, Russia under Putin, China under Xi, and Iran under the ayatollas, but also to some extent a Western policy plagued by inconsistencies and mistakes such as NATO's expansion eastwards. While pessimistic about the immediate future, Mandelbaum is more optimistic about the long-term prospects for a revival of peace. The revisionist states have failed to establish a system that ensures the continued economic growth necessary to satisfy a majority of the population. Prevailing global trends favor democratic governance even in these states, in spite of the determined efforts of the regimes in power to forestall such a development. This will not eliminate conflicts of interest among nations, but it will erode the confrontational nature of these disagreements and promote policies of compromise. The message of this book is that the world has a formula for peace, though it has no way of ensuring that all countries embrace it. The author makes a convincing case based on insightful analysis and broad historical knowledge, somewhat surprisingly with little if any cross-referencing to the quantitative literature that promotes a similar message.