Expert Commentary

Polarized America: The dance of ideology and unequal riches

2006 Princeton University study on the relationship between growing income inequality and increasing political divisions in the United States.

The past 25 years in the United States have been marked by growing income inequality, increasing political divisions and rising immigration. A 2006 Princeton University study, “Polarized America: The Dance of Ideology and Unequal Riches,” looks at possible connections between these trends.

The study’s results, published in The Journal of Politics and subsequently published as a book, were based on states’ political attitudes, income inequality levels and votes by senators and congressional representatives from the early 1970s to the mid-2000s. Other data examined included public opinion polls, census data and campaign finance records.

The findings include:

  • Polarization and income inequality fell in tandem from 1913 to 1957 and partisan divisions became increasingly blurred. From 1977 on, both political divisions and income inequality grew simultaneously.
  • As a state’s income inequality rises, the congressional voting patterns become more partisan — Republicans shift farther right, while Democrats move to the left.
  • Citizens with strong partisan identifications are more likely to apply ideological labels to themselves and are the most likely to define politics in ideological terms.
  • Higher-income citizens are more likely to identify with and vote for Republicans than are lower-income voters, a consequence of the party’s increasing embrace of economic libertarian positions.
  • Rising immigration has facilitated the move to the right. While noncitizens are a larger share of the population, they cannot vote. “This has the effect of moving the median income voter closer to the mean income citizen, reducing the demand for [income] redistribution,” the author states.

In summary, the author writes, “High levels of income inequality generate high levels of political polarization in state electorates, and both income inequality and political polarization exhibit a strong influence on partisan polarization.”

Tags: poverty, inequality

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