"It is an axiom of American life that advantage should be earned through ability and effort. Even as the country divides itself at every turn, the meritocratic ideal--that social and economic rewards should follow achievement rather than breeding--reigns supreme. Both Democrats and Republicans insistently repeat meritocratic notions. Meritocracy cuts to the heart of who we are. It sustains the American dream. But what if, both up and down the social...