Sure, America is (or at the very least WAS) the land of opportunity but that opportunity is not particularly equal. Still its probably more equal than most other places on earth.
Lind also addresses the racial aspect in TNAN:
The chief danger confronting the twenty-first century United States is not Balkanization but what might be called Brazilianization. By Brazilianization I mean not the separation of cultures by race, but the separation of races by class. As in Brazil, a common American culture could be indefinitely compatible with a blurry, informal caste system in which most of those at the top of the social hierarchy are white, and most brown and black Americans are on the bottom – forever. Behind all the boosterish talk about the wonders of the new American rainbow is the reality of enduring racial division by class, something that multicultural education initiatives and racial preference policies do not begin to address.
In the absence of sustained popular pressure from below or concern about America’s international status, the white overclass has no incentive to combat Brazilianization in the United States. For one thing, any serious effort to reduce racial separation by class would inevitably mean higher taxes on the affluent – not just the rich, but the politically powerful upper-middle class. What is more, the dominance of the white oligarchy in American politics is strengthened by the emergent dynamics of a polarized society. In a more homogeneous society, the increasing concentration of wealth and power at the top might produce a populist reaction by the majority. But in a society like that of present-day America where a small, homogeneous oligarchy confronts a diverse population that shares a common national culture but remains divided along racial lines, the position of the outnumbered elite can be very secure. This is because the resentments caused by economic decline are likely to be expressed as hostility between the groups at the bottom, rather than as a rebellion against the top. In the Los Angeles riot, black, Hispanic, and white rioters turned on Korean middlemen, rather than march on Beverly Hills.