If you pay much attention to politics in the U.S., especially during this presidential election year, you’ve probably heard someone assert that politics is getting more polarized — that is, that there is less consensus and fewer people in the middle, making it more difficult to agree on policies or get anything done. But is it true?
A recent Pew poll sent to us by Katrin indicates that it is. The Pew Research Center has tracked responses about 48 political values for over 25 years now. Over time, the percentage-point gap between Democrats and Republicans has nearly doubled:
Which issues do Republicans and Democrats most disagree about? Providing a social safety net, environmental protection, the role of labor unions, the role of government in ensuring equal opportunity, and the overall scope of government had particularly large gaps, and all have grown substantially since 1987:
Political scientists Keith Poole and Howard Rosenthal looked at polarization among federal legislators from the late 1800s through 2011. If we look at party means for members of the House, we see that after a decrease in polarization mid-century, the gap has increased again since the 1980s. Though Democrats have become somewhat more liberal, the change is is largely due to Republicans in the House becoming more conservative on average:
David Roberts posted about the trend at Grist. The changes we’re seeing in the Pew data, he argues, are not due to big value changes among the electorate. Instead, we see that people are sorting themselves politically in a more consistent fashion. The parties used to contain coalitions that united liberal and conservative voting blocs, but both parties are becoming more ideologically consistent.
There are Blue Dog Democrats, who are more conservative than the party overall, and some moderate Republicans who are fairly liberal on social issues. However, there is less and less room for these individuals. Those seeking elected office find it difficult to win primaries within their parties. Citizens increasingly associate conservatism with Republicans and liberalism with Democrats, and choose their party affiliation accordingly. Thus, without any great change in the actual values of Americans, we get a more starkly politically divided nation and federal legislature.