USAns like to pretend that social class doesn't exist, because meritocracy. That doesn't describe what we actually have, though. Meritocracy would require that everyone start at the same level - of wealth, of privilege, of safety and health and education and food.
Instead, we have meritocratic ideals, a few meritocratic policies, and a distinctly uneven playing field, which does not result in a meritocracy. Wealth buys political power which consolidates wealth, and we end up where we are, with a very clear distinction between the 1% and all the rest of us.
The Economist often runs interesting pieces it. Perhaps the most surprising finding is that, in the past few decades, we have had far higher social mobility in Europe than in the US.
Gender and minority status are often mentioned as factors that influence success potential, but social class is seldom mentioned.