In the comments sections of one of my Tribal posts, Cold Pizza linked to a long but excellent article on the Rand Corp site about tribalism and its effect on societal development. The article in turn references much research and commentary on the topic, which gives me new places to look for information. This is a more academic treatment, contrasting tribes and clans with networks and hierarchies with more precise definitions than I use in my offhand way here.
I was pleased to understand it well enough to have objections, which I will not share presently.
In my observation that one source of the A&H disdain for the Business and S&T tribes may be competitiveness, I had originally thought of this only in terms of money envy. I had followed the stereotype that the latter tribes made more money, but had less education than A&H. It turns out that they have as much education as the A&H tribe, suggesting that they are indeed beginning to supplant them as the public intellectuals. This is likely quite provoking to a group which has considered itself the natural leaders and advisors of the society.
This led me to the thought that the struggle I am observing, though it has folks acting tribally, may have more elements of a class struggle.
I am going to move away from the "types of thinking" interpretations. They are perhaps more valuable when considering the actions of an individual, but I am trying to get a handle on groups here.