The argument that "slavery is over," "segregated drinking fountains are gone" is disingenuous. I am not talking about the institutions, which can be created or abolished on the dot of midnight by the stroke of a pen. I am talking about the EFFECTS of the institutions on real people - - if you dehumanize a human being in all the ways that a human being can be dehumanized by pernicious institutions like slavery and Jim Crow and Lynch Law, and then one day in one legislative act, those institutions are abolished, do you really think that the human being that those institutions shaped is also abolished from one day to the next, by the legislation, and a new human being magically appears in her place?
If generations of slavery, Jim Crow and lynching created a young girl who "knew her place," was convinced in her bones of her own inferiority, lacked all self-esteem and knew better than to try, because trying would always end in defeat and disappointment, do you really think that the passage of the Voting Rights Act radically changed her personality in any way? It didn't, she and her family were not ideal parents for a huge complex of reasons and the children they raised had multiple problems that left them unfit to cope on many levels the way whites would cope, and their children had the same problems.
It's an intergenerational problem, and I want to be clear that the problem is not the presence or absence of the institutions of racism, it's the effect that those institutions had on the human sould. Those are permanent scars and wounds, and that many, many blacks have been able to cope with them and triumph over them on their own, without affirmative action, in the worst days of segregation, lynching and Jim Crow, is a remarkable testament to the strength of the human spirit. Just think of Rosa Parks as one woman who did NOT let Whitey rob her of her spirit or her self-respect. But realism tells us that many did not and could not rise to that challenge, but fell back, wounded and scarred and raised children with little or no motivation to learn, no love of learning, no self-respect, no real hope of betterment. And it's for those victims of white racism that affirmative action is a necessity, a moral necessity for the white racist Americans or their descendants to make some kind of amends and in more practical terms a necessity if the lingering effects of American racism are to be eliminated so that every American citizen is free of the psychological barriers or at least one of them, that kept him or her from reaching their fullest potential as individuals and contributing the maximum that they are potentially able to contribute to American society.