That is not how dark matter works at all!! Its sole defining property is that it is really crappy at interacting with things! Its not going to form planets! GAH!!! <rant/>
Fantasic article! Lots of interesting thoughts.
Rather lengthy, though, isn't it? I feel that, lurking somewhere in this enormous stream-of-consciousness essay, there is a post about 1/2 the length that could become a truly classic blog post.
Traditional anthropological ingroups and outgroups are defined by "random" characteristics: ethnicity, language, religion, dress, etc.
Many previous well-known essays and studies have pointed out that the primary difference between Blue and Red is that they perceive ethics (not just ingroup traditions/taboos/etc. and folkways) differently.
In the modern day, if not the past, we can tolerate outgroups that have different taboos (eating shellfish), have different mandatory standards of politeness (bowing, formal versus informal address to seniors and strangers), etc.
In the modern day we have narrowed down the set of things where it is acceptable to take the high moral ground on differences.
It's no longer ok to hate (or even disapprove) on the basis of differences in ethnicity, language, religion, etc.
But there are still other morals; for most Reds it's acceptable to disapprove various things that have become unacceptable to disapprove to Blues, and both parties regard the other side as immoral on those points.
I fault the current article for not taking into account those past essays and studies.