Book excerpt: We live in a period of uncertainty about the fate of America's global leadership. Many believe that Donald Trump's presidency marks the end of liberal international order-the very system of global institutions, rules, and values that shaped the international system since the end of World War II. Exit from Hegemony, Alexander Cooley and Daniel Nexon develop a new approach to understanding the rise and decline of hegemonic orders. They identify three ways in which the liberal international order is transforming. The Trump administration, declaring "America First," accelerates all three processes, lessening America's position as a world power.