From Historical Polarization to the Left Turn: Explaining Party System Responsiveness in South America

In terms of their responsiveness to voter preferences, South American party systems that experienced prolonged periods of ideological conflict in the first half of the 20th Century continue to differ starkly from those in which elites avoided or where military coups ended polarization. The duration in historical polarization constitutes a critical juncture that sets Uruguay, Chile, and Argentina apart from the rest of South America. While not fully determining the paths party systems have taken at later critical junctures, this basic distinction between two types of party systems has survived the authoritarian regimes of the 1960s and 1970s, the "neoliberal critical juncture" of the 1980s, and for the most part also the subsequent "left turn". This paper first presents the theoretical and empirical foundations for this argument. It then uses data on party positions and voter preferences to show how autocratic-democratic regime divides in the aftermath of authoritarianism have nurtured new programmatic alignments in Brazil, Bolivia, and Mexico. The final part of the paper reflects on whether Latin America’s "left turn" may have triggered the formation of a new cultural divide in countries governed by the moderate left during the "left turn".