Professor's tend to have very narrow fields of study and often their views try to bend reality to fit through their particular field. In this case, it sounds like a somewhat standard (as in common place) form of Marxism -- wherein most all societal concerns are driven by classism (and ultimately economic concerns).

Hogwash. Now, Professor Stearns almost certainly has valid, well researched points which we could use to adjust certain policies, but humans are very much more than economic creatures , though it seems like we forget this readily nowadays in the US. This also means there are many more factors influencing American societal and mores than class divides. There's many strong cultural factors driving various network effects and topologies which require more complex analysis to understand. E.g. trying to use a first level "approximation" will fail to rationally understand our society. Besides in places like California even the idea of a white/Caucasian majority isn't even valid anymore.