Abstract
<p>In less than a generation, Argentina has gone from being one of the least polarized democracies in the comparative CNEP dataset to one of the most—simultaneously along ideological and affective lines. For most of its democratic history, political conflict ran along a single axis: Peronism versus anti-Peronism, the grieta, largely detached from the left–right divide that organized competition across the rest of Latin America. This chapter shows how, over the past three decades, that cleavage has progressively fused with a left–right ideological axis, and how this fusion did more than sharpen disagreement—it charged it with emotion. Drawing on longitudinal survey data (Latinobarómetro 1996–2024; CNEP Argentina 2007 and 2023/24) and multilevel and OLS models, we trace this transformation to radicalization, party sorting, and rising income inequality.Our central claim is that ideological and affective polarization are not parallel trends but a single, self-reinforcing process, and that the arrival of Javier Milei is its clearest expression. The "Milei effect" pulled the entire right pole toward more extreme positions and, crucially, offered voters a crisp, unambiguous ideological signal. It is precisely this clarity that fuels emotional intensity: voters who successfully locate their party on the ideological map develop the strongest affective reactions toward their rivals. Argentine polarization is therefore not irrational tribalism but ideologically structured partisanship. In this respect, Argentina is less an exception than a vivid case of a dynamic now unsettling democracies worldwide—where the radical right supplies the ideological clarity that turns disagreement into animosity, with corrosive consequences for governance, social cohesion, and democratic stability.</p>