Matt Yglesias seems a bit surprised to find that polarization doesn’t always break on partisan lines but on ideological ones, looking at the example of Martin Luther King Jr. and George Wallace, who were both Democrats. But polarization isn’t limited to Red Team/Blue Team parameters, as set out by the DC press corps. King was a liberal, Wallace was a conservative. Moreover, on the issues of segregation and civil rights, King was the leading advocate for change and Wallace a leading obstacle for the change King sought. Wallace and his supporters – all conservatives, but of both parties – used violence, intimidation, and assassination as tools to fight civil rights. King preach non-violence and civil disobedience as a means to challenging segregation in America.

I do think Yglesias gets that ideology is a larger driver of polarization than partisan identification. But it cuts the other way as well. Just because Loughner may not have been citing his desire to vote for Sarah Palin for President doesn’t mean he wasn’t a conservative. And at heart, the GOP has played the Tea Party as a conservative movement, not a Republican one. If you doubt that, just ask the Tea Party, which goes to great lengths to say they aren’t a Republican front. The driving factor in the Republican base, the thing that their leaders speak to, is conservativism, not Republicanism. And so when events like this weekend’s assassinations happen, it is not relevant whether the shooter espouses Team R for Republican leaders to be culpable, only conservative ideas. While details are still emerging, it does seem like Loughner comes from the fringe areas of the conservative movement. The rhetoric on trial should rightly be viewed as conservative, not Republican.