The fall of the Berlin Wall exposed the failures of Soviet communism. Now, writes Kimmage, “it is a wavering West that is on trial.” Defending the West—which he defines as a geopolitical and cultural concept rather than a geographic place—has been the animating core of U.S. foreign policy since the beginning of the twentieth century. Kimmage traces the rise of the concept in the first half of the century and then its gradual decline under criticism from both the left (which saw the paradigm as too white and too imperial) and the right (which saw it as too multinational), through to its evaporation after the end of the Cold War. Presidents once routinely touted the West in their speeches, and universities required introductory courses in Western civilization. No more. Kimmage outlines the costs of this loss: the idea had provided a reason for international engagement, a compass for dealing with authoritarian challenges from states such as China and Russia, and a broader guiding principle for U.S. foreign policy.