“Soak the rich!” has been a popular plea among citizens, politicians, and philosophers for centuries. But the main rationales for doing so have varied. This fine model of social science research explores the history of income and inheritance taxes in 20 North American and European countries and critically evaluates several hypotheses for why there have been such great differences within and between countries. Although advocates for taxing the wealthy at high rates often invoke “fairness,” ideas about what is fair differ greatly. Through careful statistical analysis, Scheve and Stasavage reject the most common explanations for why governments choose to impose high rates on the rich—for example, to address rising inequality. They conclude, instead, that the most common justification is “comparable sacrifice,” a rationale that has proved especially successful immediately after periods of heavy military conscription, which often disproportionately affects the poor and leads to calls for “wealth conscription.” Corporations, however, seem mostly immune to this dynamic, which helps explain why globalization has led to greater overall declines in corporate tax rates than in the rates applied to high-income individuals.