Class is a suppressed concept in America, although the loathsome big business community there has lots of class consciousness. The understanding of class struggle is a surprisingly useful insight into current affairs though, as used correctly it often identifies the core conflict at the root of political disputes.
This article in The Guardian identifies individual stories of upward class mobility, noting the differences in the livelihoods of those who advanced up the socioeconomic ladder. Karl Marx’s theory of alienation can perhaps be applied differently to wealthy professionals that have advanced up, since (as the article relates) those with much higher incomes can lose — become alienated from — the friends they once had with lower socioeconomic status. Such is another consequence of the dysfunctional economic system currently operating.