The centenary volume of the American Science Political Review looks at the evolution of the discipline. Mark Blyth on comparative politics:
Political science’s inability to predict any of the great events of the previous decade had proven a serious embarrassment. Eager to make up for their prewar irrelevance, post-war political scientists sought to provide policymakers with predictions regarding, as Gabriel Almond put it, “exotic and uncouth” parts of the world (Almond and Coleman 1960, 10). As Karl Lowenstein (1944) wrote, to overcome past errors comparative politics would have to become “a conscious instrument of social engineering” (541) because “the discipline ha[d] a mission to fulfill in imparting our experience to other nations integrating scientifically their institutions into a universal pattern of government” (547). Political science therefore had to become positive and predictive, and the discipline rebuilt itself around the latest theories of the day (functionalism, modernization theory, and political culture) to meet these new expectations.
This new version of political science posited that societies were self-equilibrating entities that shared common functionally related subsystems for integration, adaptation, and goal attainment.Actually existing societieswere then arrayed along a developmental continuum with the United States posited as the world’s historical end. Where states actually sat on this telos was determined by some combination of their functional fit (Huntington 1968) and/or political culture (Almond and Verba 1966). Some political cultures were seen as better or worse at adapting to the dictates of modernity, but overall the path to a stable capitalist democracy was pretty much set. At least this is what members of the discipline imagined into the 1960s, a decade that proved to be, just like the 1920s and 1930s, a watershed for political science. As occurred in the 1920s and 1930s, these new and scientifically rigorous theories were about to be punctuated (and thereby invalidated) by the politics of the day.