"The U.S. is steadily separating into a two-caste system with marriage and education as the dividing line. In the high-income third of the population, children are raised by married parents with a college education; in the bottom-income third, children are raised by single parents with a high school degree or less."
A major obstacle is that most low-income women plan to marry after having children, not before. Their life plan is the exact opposite of the normal sequence in the upper middle class. In the upper middle class, men and women still follow the traditional pattern: A man and woman become attracted to each other; a relationship develops; the couple assess each other and at some point deliberately choose to become lifetime partners; emotional bonds deepen; they marry and after a few years have children.
"In the lowest-income third of the U.S. population, this traditional sequence of family formation and childbearing is now explicitly reversed. Women first have children and then seek to find or build a stable relationship that will eventually lead to marriage. Typically, low-income single mothers do not see marriage either as an important part of childrearing or as an important element of financial security or upward social mobility. Instead, marriage is seen as a symbolic event that should occur later in adult life. Marriage is regarded as an important ceremony that will celebrate one’s eventual arrival in the middle class rather than as a vital pathway that leads upward to the attainment of middle-class status."