A theory may distort our understanding of historical phenomena for two reasons. Perhaps a perfectly sound theory has been misapplied in the particular instances. Alternatively, the failure of those who use the theory may reveal weaknesses in the theoretical structure itself. Pluralism has failed to explain McCarthyism, agrarian radicalism, and the relation between them. We will first review the evidence that refutes pluralist interpretations of these movements. We will then examine the defects in the general theory of pluralism that have contributed to its specific failures here.
Pluralist interpretations of McCarthyism and agrarian radicalism suffer from four misconceptions. First, the pluralists see a continuity in support that does not exist and misunderstand the evolution of American politics. Second, they exaggerate the "mass" character of McCarthyism and misinterpret the "mass" character of the agrarian radical movements. Third, they minimize the importance of the specific issues with which McCarthy and the agrarian radicals sought to deal. And fourth, they fail to understand the role of moralism in the American political tradition.
The difference in electoral support between McCarthyism and agrarian radicalism is easiest to demonstrate objectively.