Now, I’m the sort of idiot who makes the same mistake twice. So to the list of the most significant political events of the postwar era I want to add this candidate — the death of Rock Hudson.

Throughout his long and successful acting career, Hudson had kept a secret — that he was a homosexual. He denied persistent rumours and even married the secretary of his homosexual agent in order to provide cover for his promiscuous gay lifestyle. In 1984 when the star had Aids diagnosed, his spokesman claimed that it was liver cancer.

Then, one year later, came the admission. The speculation was true. Hudson, his spokesman said, was indeed dying of Aids. Although he continued to claim that the cause was a blood transfusion, Hudson’s acknowledgement helped to change the politics of homosexuality for ever. Hudson’s death, the death from Aids of a heterosexual icon, was the beginning of the end for “don’t ask, don’t tell”.

In his superb book Virtually Normal, the journalist Andrew Sullivan recounts how for much of the post-war era homosexuals “could be fully integrated so long as they never disturbed the public conventions of discretion. They were confirmed bachelors or spinsters, funny uncles and eccentric aunts, prickly brothers, or just village characters.” They weren’t asked and they didn’t tell.

Then came Aids. “Suddenly the funny Uncle at Thanksgiving was sick; and it was obvious why and how.” Soon the subject of homosexuality was unavoidable; some gays, like Hudson, became unable to disguise their identity while many others simply became unwilling to do so. As Sullivan puts it: “The compact between heterosexuals and homosexuals had to be renegotiated.”

And it has been, at least in Western liberal democracies. The insistence on asserting gay identity has changed so much — an equal age of consent, the introduction of civil partnerships, gay MPs and Cabinet ministers, the creation of a vibrant, open gay culture. And while some may regard the collapse of “dont ask, don’t tell” as something of a disaster, I think most regard it as an advance. Certainly I do.

All of which makes the fuss over Ruth Kelly’s new Cabinet job deliciously ironic. Ms Kelly has been given a mish mash of responsibilities, which include that for equality. The result has been a great deal of ado about her strict Catholicism, which is thought to mean that she believes homosexuality is a sin.

I employ the word “thought”, because she refuses to say what she believes. She appreciates that if she stated publicly what everyone knows to be her religious view, she would not survive the ensuing row. She is right, too. The putative European Commissioner Rocco Buttiglione told members of the European Parliament that he thought homosexuality was a sin, and that was the end of him.

So, once it was homosexuals who had to employ “don’t ask, don’t tell” to survive in public office. Now it is Roman Catholics. How much better is that?

Ms Kelly’s critics say that the problem is not with her, but with the office she has been appointed to. I do not believe them. There was a fuss when she was made Education Secretary (how can she look after stem cell research and sex education?). Clearly she couldn’t do Health (abortion) or Northern Ireland (where do I start?) or Culture, Media and Sport (Christian radio stations) or the Home Office (community relations) or the Treasury (VAT on rosary beads). Maybe a post in which she was paid to have unprotected sex would be acceptable, but we already have a Deputy Prime Minister.

I believe Ms Kelly is wrong about homosexuality. It is not a sin. I do not agree with the orthodox interpretation of the Bible. After centuries of study and prayer I think we are entitled to argue that we now have a better understanding of God’s will. I think that the respect and legal protection now afforded to gay people is one of the greatest advances of modern society.

Yet I also respect orthodox religious faith, with the dedication and learning that so often accompanies it. Orthodox religious doctrine does not allow its followers the luxury of picking and choosing. Adherents cannot easily declare UDI on a passing issue that takes their fancy.

And my respect leads me to this — that if Ruth Kelly were to be allowed to express her religious views publicly and remain in office we would all, gay people included, gain by it.

A public declaration would allow us to demonstrate that in this country there is a difference between Church and State. And it would allow us to show, too, that we understand one of the most important of differences — that between a sin and a crime.

The essence of a liberal society is that we all accept that others should be free to do things and say things that we don’t approve of. I have my own list of things that I dislike intensely — Big Brother, beetroot and Noam Chomsky for instance — but I don’t want them to be outlawed or discriminated against.

For our Equality Minister to be a woman who disapproves openly of the very thing that she is protecting would be the most eloquent possible statement that we are a liberal society.

In 1960 in West Virginia John F. Kennedy decided to confront doubts over his religion. He didn’t see why a Catholic should be barred from the presidency. When he won he declared that “the religious issue had been buried here in West Virginia”. If only he was right.

daniel.finkelstein@thetimes.co.uk

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