Growing US Partisanship

I think you want to read this excellent post by Jonathan Chait. That is all.


US partisanshipe appears to be the meme of the day. Dana Milbank (who is very different from Chait) also wrote about it. Milbank cites a different academic study. From the brief summaries both academic studies sound very convincing to me.

update 2: yep it’s a meme. Charlie Cook too.

update 3: Dan Balz too

end update 3

One of the more interesting changes in U.S. politics in recent years has been the increasingly parliamentary nature of voting behavior. Fewer people are straying beyond their party affiliations, we are seeing more straight-ticket voting, and the characteristics of individual candidates mean less than ever

end update 2.

I was intrigued by this passage in Milbank’s column

“Also of note is that the partisan polarization occurs even though Americans aren’t all that split on policies or ideology. Their partisanship is more tribal than anything — the result of an ill-informed electorate. ” Milbank supports this claim with a quote from Sean Westwood (one of the academics). I clicked the (pdf warning) link to the academic article. I am going to guess that the non split on politicies and ideology is of the following form — partisan Republicans agree with Democrats that rich people should pay higher taxes and that Medicare and Social Security should be expanded not cut. In other words I dare guess that the evidence of a tribal ill-informed electorate who hate the other party even though they agree with its proposed policies is asymmetric with the evidence of irrational tribalism actually evidence of irrational tribal Republicans.

Even before I check my guess, I note that my firm belief that a majority of US Republicans are ill-informed tribal and totally confused is one more data point supporting the Chait/Milbank hypothesis. I, for one, sure am a tribal Democrat. I will now check my guess and report back.

Oooops egg on my face. I can’t find anything about ideology or policy preferences in the linked article. Westwood’s statement to Milbank must be based on other evidence.

Also the paper is fascinating. It includes actual games using real money — the dictator game and the trust game. I suggest you just click the link and scroll down to that section. The results are dramatically asymmetric. The difference between sharing with and trusting partisans of the same party and of the different party are stressed in the abstract and introduction. This is Ballanced because the authors don’t stress differences between Republicans and Democrats. But the detailed results show a more dramatic difference between Republicans and Democrats than between same party vs opposite party pairs. Republicans are less generous and trusting. Republicans are more partisan (their actions differ much more depending on whether they are playing with a Republican or a Democrat). The point estimate is that Democrats are less generous with Republicans than with other Democrats Republicans are with other Republicans, but the difference isn’t statistically significant.


In the dictator game player one (the participant) decides how to divide up some money. Given zero to the other player obviously maximizes one’s payoff, but it is rare.

Basically the asymmetry — Republicans are less generous than Democrats — is about as strong as partisanship — people are more generous with other people of the same party. Yet the symmetric result was stressed more. I think the eccellent paper shows how people bend over backwards to not appear partisan when denouncing partisanship.