America’s elite is producing children who not only get ahead, but deserve to do so: they meet the standards of meritocracy better than their peers, and are thus worthy of the status they inherit.
This is partly the result of various admirable aspects of American society: the willingness of people to give money and time to their children’s schools; a reluctance to impose a uniform model of education across the country; competition between universities to build the most lavish facilities. Such traits are hard to object to, and even if one does object they are yet harder to do anything about. In aggregate, though, they increase the chances of wealthy parents passing advantage on to their children. In the long run that could change the way the country works, the way it thinks about itself, and the way that people elsewhere judge its claim to be an exceptional beacon of opportunity.
Part of the change is due to the increased opportunities for education and employment won by American women in the twentieth century. A larger pool of women enjoying academic and professional success, or at least showing early signs of doing so, has made it easier for pairs of young adults who will both excel to get together. Between 1960 and 2005 the share of men with university degrees who married women with university degrees nearly doubled, from 25% to 48%, and the change shows no sign of going into reverse.
Assortative mating of this sort seems likely, on average, to reinforce the traits that bring the couple together. Though genes play a role in the variation of intelligence from person to person, this is not a crude genetic determinism. People tend to encourage in their children what they value in themselves and their partners. Thus people bought together by their education and status will typically deem such things important and do more to bring them out in their children, both deliberately and by lived example—processes in which nature and nurture are more than likely to work hand in hand.
SOURCE - Economist