Few political theorists today try to show how the principles of theory should guide our judgments of policy. Theorists think that their job is done when they have explained the principles, or (more commonly) when they have interpreted the principles of other theorists. The connection between the principles and the policies of governments is left for citizens themselves to make. Yet making that connection—exercising political judgment—is an essential part of citizenship, and should have a prominent place in the education of citizens.
Political theorists have not always neglected the making of judgments about particular policies. The disdain of the particular that marks much contemporary theorizing was not shared by the great theorists of the past. The tradition of theory begins (or at least the curriculum traditionally begins) with the greatest case study of all—Socrates' trial. Although later theorists usually settled for less exalted examples, they continued to see their vocation as calling for comment on the actual policies of rulers and their rivals. Recall Aristotle's letters to Alexander, Augustine's criticism of the Donatists, Machiavelli's commentary on the corruption of Florentine rulers, Hobbes' analysis of the Long Parliament, Locke's advice to the Board of Trade, or Rousseau's critique of the government of Poland.