The US has traditionally stood for a large amount of equality of opportunity, at least among whites. This implies that the success of children would depend mainly on their ability and energy, and much less so on their parents’ incomes and education. This has always been an aspiration rather than a fact, and the disturbing evidence in several studies indicates that equality of opportunity has declined by a lot during the past half century. In a recent book, Coming Apart, Charles Murray highlights this apparent fact with interesting statistics.
Another way to state what has happened during the past half century is that the degree of mobility between generations has apparently declined. The evidence suggests that children of successful parents are more likely to be successful relative to others of their own generation than was true in the first half of the 20th century. One important reason for this, I believe, is that education is now a much more important determinant of economic success than it was in 1960. Educated parents have always been much better than parents with relatively little education at preparing their children to succeed at school. This difference in preparation of children is now more important because greater education has become more necessary to succeed in the modern knowledge-driven American economy.
One approach to thinking about the causes of this trend is to divide employment opportunities into good and bad jobs. Some discussions assume, implicitly or explicitly, that the number of good jobs is rather fixed, that many individuals of different classes are capable of filling these good jobs, and hence that who gets the better jobs depends on contacts, influence, and credentials, like having a college degree. On this approach to labor markets, children of upper class parents-those with greater income and education- are more likely to succeed now than in the past because their overall education and other “credentials” have increased compared to those of children from the lower classes.