I'm Brazilian and while our country surely is racist, we never had racist laws. So I was shocked to discover that a writer called William Buckley, who apparently was respected even by his opponents, once in 1957 wrote the following in this National Review magazine:
The central question that emerges—and it is not a parliamentary question or a question that is answered by merely consulting a catalog of the rights of American citizens, born Equal—is whether the White community in the South is entitled to take such measures as are necessary to prevail, politically and culturally, in areas in which it does not predominate numerically? The sobering answer is Yes—the White community is so entitled because, for the time being, it is the advanced race.
National Review believes that the South's premises are correct. If the majority wills what is socially atavistic, then to thwart the majority may be, though undemocratic, enlightened. It is more important for any community, anywhere in the world, to affirm and live by civilized standards, than to bow to the demands of the numerical majority. Sometimes it becomes impossible to assert the will of a minority, in which case it must give way; and the society will regress; sometimes the numerical minority cannot prevail except by violence: then it must determine whether the prevalence of its will is worth the terrible price of violence.
What is this? Is this a kind of thing people would really argue for in those days? Wasn't this the kind of stuff that would bury a writer's career even in the 50's?
William F. Buckley is the writer who is famous for saying that a conservative ought to "stand athwart history yelling 'Stop!'" This quote is indicative of his political philosophy as well as his pretentious writing style, this must have been the last time anyone in America unselfconsciously used the word "athwart". He can't be seen as representing mainstream American public opinion during the 1950s. That's not to say, though, that his opinions are totally out of left field (well, for Buckley it would be right field, haw haw). I think the arguments he's making are pretty typical of pro-segregation arguments of the first part of the 20th century.
From reading the full article, it seems that Buckley is arguing that is not necessary to make sure that all citizens have the opportunity to vote because "universal suffrage is not the beginning of wisdom or the beginning of freedom", and that it is more important to "uplift" black Americans and raise their level of civilization than it is to protect their voting rights. Once black people are sufficiently uplifted, according to this theory, segregation will wither away. Buckley opposed measures taken by the federal government and judiciary to abolish legal segregation on the grounds that doing this was usurping power that belonged to state and local governments, and this is obviously an easier position to hold when you believe that segregation will fade on its own eventually, once black people (mostly black people, who Buckley calls backwards, but actually also white people too, since he suggests in this essay that whites would commit voter fraud and otherwise flip out if black voters were to choose something they didn't like) figure out "civilized standards".
The argument that segregation is necessary to raise the standard of civilization and generally prevent the South from descending into anarchy is one I associate with early 20th-century progressives, so it's funny to hear it parroted by Buckley here, but it's paired with these more familiar conservative themes about "states' rights" and the tyrannical federal government. Yes, it's startling to see someone state baldly that it is correct for white Southerners to believe that their culture and level of civilization is superior to that of their black fellow citizens, but that's an argument that was made in the 1950s. It wasn't uncontroversial, though, even in conservative circles. Apparently Brent Bozell, another important conservative writer of the era, wrote a rebuttal to Buckley's editorial in the next issue of National Review. I can't find the text of the article, but it seems that what he said was that the Fifteenth Amendment to the US Constitution extends the franchise to all citizens and that Buckley has to deal with it.