If you mean, does the United States of America practice apartheid by Federal law... No it does not, though some states maintained lingering racial-segregation laws and ignored racism until the middle of the last Century.
However, social attitidues take far longer to fade, because you cannot force people to drop particular antisocial beliefs such as mysogyny, racism, homophobia, fear of the mentally-ill or physically-disabled, religious bigotry and financial-snobbery, if their beliefs stem from dogma entrenched for generations in their own communities.
Countries can use Law to stop prejudice against people in seeking employment, etc, and many do; but erasing those dogmas at heart takes education, time and individuals' own courage and self-respect.
A PM correspondent on here illustrates the problem of ignorance, although obviously one young Utah resident does not represent all Americans! Challenging his despising of Jews in some of his messages, I ask him his evidence: none. He can offer only "It's what my Dad says", and being impressed by Adolf Hitler's oratory skill shown in old newsreels. So does not question it.
It is also clear he has very little understanding of the outside world and its 20C history (I am not sure if he was taught it at school, but is certainly indoctrinated by Hollywood); he cannot or will not question his elders' ignorance; he seems to think such naivety normal.
Which brings us back to "education" and "courage".
