Attempting to present the case for a No vote on marriage equality on ABC’s 7:30 program recently, former Woolworths CEO Roger Corbett instead gave a rambling and at times contradictory interview in which he unwittingly exposed the deeply segregationist logic beneath the right’s defence of so-called traditional marriage.

In answer to interviewer Leigh Sales’ opening question as to why he supports the No vote, Corbett began with the customary disclaimer that “-phobes” of all stripes use to distance themselves from the bigotry they’re about to spew: “Well, first of all, I would like to say that I have many gay friends …”. However many gay friends he had at the start of the interview, it’s doubtful many would have stuck with Corbett by the end.

Asked if his view is based on belief in tradition, Corbett replied no but yes, it is based on tradition, that of the Judeo-Christian tradition – a racist, conservative invention that today is often used to exclude Islam from “Western values”, of which Judeo-Christian principles are a foundation.

When Sales replied that societal views on the purpose of marriage have evolved over the centuries, Corbett fell back on arguing that there is something essential about man-woman marriage, that it is an “arrangement” in which children can be conceived and raised. While adoption, surrogacy, IVF and other ways of conceiving and raising children were wilfully ignored, the former CEO went on to argue that, of course, gay people should have a right to “a union of their own that should have equal status, equal recognition in every way, but be called something different to marriage, because marriage is between a man and a woman”.

And in one of those revelatory foot-in-mouth moments during which a person’s inner logic is laid bare, Corbett went on to say: “A man and a man and a woman and a woman can have a similar relationship, but it’s different. A black man and a white man are equal, but they’re clearly different. A black man will never be a white man and vice versa”.

It’s a statement worthy of Bull Connor, the segregationist commissioner of public safety in Birmingham, Alabama, who infamously ordered the closing of 60 Birmingham parks rather than comply with a federal court order to desegregate public facilities. In 1963, when defending his use of fire hoses on African-American youth demonstrating for civil rights, Connor said, “You can never whip these birds if you don’t keep you and them separate. I found that out in Birmingham. You’ve got to keep your white and the black separate”.

The logic behind Corbett’s argument against marriage equality is that of “separate but equal”, a doctrine used in the United States until 1954 to uphold racial segregation laws for public facilities such as schools, public transport and recreational facilities. The phrase came from the 1896 US Supreme Court ruling in Plessy v. Ferguson, after Homer Plessy, a “mixed race” man, was arrested for riding in a whites-only train car.

The “separate but equal” doctrine legitimised Jim Crow in the south, a set of laws that gave Blacks and whites separate facilities, separate parts of cities to live in, separate employment and separate rights. Jim Crow started to appear in southern states after the adoption of the 13th and 14th amendments to the US constitution, outlawing slavery and granting equal protection to all US citizens under the law respectively.

Jim Crow recast newly freed Blacks as second-class citizens, finding ways to discriminate against them even after they had achieved legal emancipation. “Separate but equal” held that, so long as all public facilities provided were equal, they could be segregated by race without violating the 14th amendment.

But separate was never equal, a fact most apparent in education. In 1930, for every $37 spent on a white child’s education in Alabama, just $7 was spent on a Black child’s. In Georgia, it was $32 for every white child and $7 for every Black child. In Mississippi, it was $31 to $6. And in South Carolina, the state spent $53 and $5.

Black teachers earned 60 percent of a white teacher’s salary, and the white school term was about two months longer, which added to the salary gap and also ensured white pupils spent more time learning.

The outcomes of this segregated education system were anything but equal: literacy rates for African-Americans were about 70 percent compared to 90 percent for whites. More importantly, few among the Black population who the federal Census Bureau identified as literate stayed at school beyond primary school. If they did complete their education, they were barred from entry into universities.

The doctrine of separate but equal was eventually overturned in the 1954 Brown vs Board of Education decision, which stated that “separate educational facilities are inherently unequal”. The struggle of African-Americans for civil rights throughout the 20th century to ensure that desegregation was not only in place in law but also enforced in practice was key to finally ending Jim Crow.

The idea that separate can ever be equal is rightly seen as a weak justification for continuing discriminatory practices. Today, in the Australian marriage equality debate, the argument for separate civil unions for same sex couples is a shallow argument that the right uses to mask its homophobia.

Civil unions do not automatically grant couples the same rights as marriage in areas such as parenting, migration law and next of kin rights. Importantly, while civil unions might be recognised in one state, they might not be in another.

However, the argument for separate institutions based on some seemingly essential factor, such as sexual orientation, enshrines discrimination within the law, rendering these institutions inherently homophobic.

In 1967, Mildred and Richard Loving, an African-American woman and a white man, won the right to be married after they had both been sentenced to a year in prison for violating the state of Virginia’s anti-miscegenation laws. In the Supreme Court ruling on the case, the chief justice said:

“Marriage is one of the basic civil rights of man … To deny this fundamental freedom on so unsupportable a basis as the racial classifications embodied in these statutes … is surely to deprive all the state’s citizens of liberty without due process of law.”

In 2007, on the 40th anniversary of the court’s decision, Mildred Loving drew the link between her struggle for the right to marry the partner of her choice and the struggle of LGBTI people for the same right:

“I believe all Americans, no matter their sexual orientation, should have that same freedom to marry … I am still not a political person, but I am proud that Richard’s and my name is on a court case that can help reinforce the love, the commitment, the fairness and the family that so many people, black or white, young or old, gay or straight, seek in life. I support the freedom to marry for all.”