Tipping Point for Legislative Polarization

A predictive model of a polarized group, similar to the current U.S. Senate, demonstrates that when an outside threat – like war or a pandemic – fails to unite the group, the divide may be irreversible through democratic means. Published today in the Proceedings of the National Academy of Sciences as part of a Dynamics of Political Polarization Special Feature, the model identifies such atypical behavior among the political elite as a powerful symptom of dangerously high levels of polarization. "We see this very disturbing pattern in which a shock brings people a little bit closer initially, but if polarization is too extreme, eventually the effects of a shared fate are swamped by the existing divisions and people become divided even on the shock issue," said network scientist Boleslaw Szymanski, a professor of computer science and director of the Army Research Laboratory Network Science and Technology Center (NeST) at Rensselaer Polytechnic Institute. "If we reach that point, we cannot unite even in the face of war, climate change, pandemics, or other challenges to the survival of our society." The model – essentially a game that simulates the views of 100 theoretical legislators over time – allowed researchers to dial up party identity, intolerance for disagreement, and extremism to levels such that almost no degree of shock could unite the legislative group. In some situations, the simulation revealed that even the strongest shock fails to reverse the self-reinforcing dynamics of political polarization.