The socio-cultural differences are obvious. Working-class black Americans speak a different dialect of English than working-class whites. They belong to different churches, mostly all-black churches. They usually live in black-majority neighborhoods. Even today, they rarely marry outside their racial group. Most of a black’s friends will be black, at least at the working-class level. The blacks have their own distinctive cuisine, customs, myths. “It’s a black thing, you wouldn’t understand.”
To point up a contrast, American Jews have become much more assimilated to mainstream culture. Forty or even thirty years ago Jews, even the wealthiest of them, formed a separate, parallel social class from the Anglo-Saxon elite. They had their own distinctly Jewish educational institutions, organizations, law firms and financial companies. They were not welcome in respectable hotels, they were not welcome in most elite country clubs, and they were only grudgingly welcome in Ivy League schools. An elite Anglo who married a Jew would risk ostracism, even from his or her immediate family. None of these things are true any longer. The Jews have kept their religion and some of their customs, but they are now full, unconditional members of American society, and rich Jews are full, unconditional members of the white overclass, with free intermarriage back and forth. Blacks – at all class levels – have a long way to go before they reach that point.