Communist revolution happened in Russia but not in the West, because of class.
In the Marxist universe, if you are born in the working class, you can never rise to the upper class, no matter how smart and driven you are. Where this is true, smart guys who feel blocked from rising become revolutionaries.
In the US, it has long been both perception and reality that a smart and capable person can come from working class parents and become wealthy.
This is why the Liberal Leftists want current generations to pay for the sins and evil of the past. In European and Asian countries, you are expected to pay for your family’s sins and debts. This often why people cannot rise above their raising.
In America, we are only responsible for OURSELVES!! And we can literally be as successful as we are willing to work towards!