The operation of markets and of politics are in practice deeply intertwined. Political decisions set the rules of the game for market competition and, conversely, market competitors participate in and influence political decisions. We develop an integrated model to capture the circularity between the two domains. We show that a positive feedback loop emerges such that market power begets political power, and political power begets market power, but that this feedback loop is bounded. With too much market power, the balance between politics and markets itself becomes lopsided and this drives a wedge between the interests of a policymaker and the dominant firm. Although such a wedge would seem pro‐competitive, we show how it can exacerbate the static and dynamic inefficiency of market outcomes. More generally, our model demonstrates that intuitions about market competition can be upended when competition is intermediated by a strategic policymaker.

Polarization is both a description of the current state of politics and a dynamic path that has rippled across the political domain over decades. We provide a simple model that explains why polarization appears incrementally and why it was elites who polarized first and more dramatically, whereas mass polarization came later and has been less pronounced. We incorporate an ostensibly unrelated finding about how voters form preferences into a dynamic model of elections. This change, when combined with the response of strategic candidates, creates a feedback loop that can replicate many features of the data. We explore the model’s implications for other aspects of politics and trace what it predicts for the future of polarization.