Andrew Cherlin, a sociologist at Johns Hopkins, as quoted by Thomas B. Edsall in a
New York Times column on the topic of what causes poverty.
A bachelor’s degree is the closest thing to a class boundary that exists today.
Edsall combines a variety of potential poverty causes into a narrative that resembles a death spiral:
Automation, foreign competition and outsourcing lead to a decline in well-paying manufacturing jobs, which, in turn, leads to higher levels of unemployment and diminished upward mobility, which then leads to fewer marriages, a rise in the proportion of non marital births, increased withdrawal from the labor force, impermanent cohabitation and a consequent increase in dependence on government support.
I'd add that millions of illegal immigrants - willing to work for less (and not unionize) - take many of the manufacturing jobs that remain.