RealClearPolitics ^ | May 11, 2012 | Sean Trende
Thomas Mann and Norm Ornstein ignited a bit of a firestorm with their column describing Republicans as main drivers behind Washington's problems. The Washington Post's Chris Cillizza has made some excellent points with regard to Mann and Ornstein's qualitative arguments, and other thorough responses abound. Rather than revisiting these points, I would like to focus my attention on the quantitative arguments made at the end of the article. Mann and Ornstein note that:
“[P]olitical scientists Keith Poole and Howard Rosenthal, who have long tracked historical trends in political polarization, said their studies of congressional votes found that Republicans are now more conservative than they have been in more than a century. Their data show a dramatic uptick in polarization, mostly caused by the sharp rightward move of the GOP.”
Again, to illustrate this point, DW-NOMINATE suggests that Congress became much less polarized in the 1920s and 30s, which is probably true. But it suggests that both parties moved toward the center (and that both Northern and Southern Democrats, on average moved toward the center). There simply isn't any support for the idea that the Democrats in the 1936 Congress were, on average, more conservative than Democrats in the 1926 Congress, at least in the sense that contemporary pundits use the term. But as the agenda moved leftward, the rise of the Conservative Coalition has the effect of pulling both parties toward the center, even though, overall, both were probably becoming more liberal.
DW-NOMINATE remains a powerful tool, especially if you keep its limitations in mind and are looking at discrete Congresses (or really are interested purely in polarization). It even sheds interesting light on realignment theory. But it really doesn’t do any of the things the popular press is claiming it does, at least not particularly well.
(Excerpt) Read more at realclearpolitics.com ...
