Us vs Them political polarization in Latin America has been rising since 2000 in keeping with global trends, but faster than world averages since 2015. Comparative research shows that not only are political divisions growing globally, but also that, once a society becomes divided into mutually antagonistic political camps (i.e. pernicious polarization), democratic erosion is likely to ensue. The article examines dynamics of political polarization and its consequences for democracy in the region. A new framework of democratic resilience argues that the degree of agreement in four critical arenas influences a democracy’s capacity to withstand, adapt or recover from external stressors and polarizing agents, without succumbing to pernicious polarization and democratic decay. These arenas are the boundaries of community membership, the concept of democracy, the terms of the social contract, and levels of inequality, which themselves become the fault lines of polarization when agreement on them is absent or weak.