It is not easy for a man to make a serious political point on the shortcomings of the new Civil Partnership Bill while he is wearing half a wedding dress and calling himself Miss Panti. Last weekend Panti was the parade host for the annual Pride rally, now officially the LGBTQ Pride Festival, with the abbreviation used to include the entire lesbian, gay, bisexual, transgender and queer community.

Unclear as to the relevant pronoun, newspaper coverage simply referred to Miss Panti throughout, rather than “he” or “she”, while blandly reporting that the speaker was “also known as Rory O’Neill”.

I’m going to take a leap in the dark here, though, and assume that O’Neill is a bloke. He told the crowd that while opinion was divided in the LGBTQ community on whether the new bill was a stepping stone to full equality, or a second-rate sop to their demands, “all agree that [it] does not go far enough”. Panti reminded the 12,000 marchers that “anyone can get married in this country except you; any soccer hooligan, any gay-basher, any fascist, any murderer, any sex offender”.

Not entirely true. For a start, the Gay and Lesbian Equality Network is enthusiastic about the bill and the comprehensive protections and recognition it provides for same-sex couples in Irish law. In almost every respect it places such couples on a legally identical footing with heterosexual married pairs.

But it’s the omissions in the bill, rather than those provisions that would have been utterly unthinkable even a decade ago that have irked the more vocal campaigners. They want to be able to marry, with exactly the same status and ceremony as heterosexual pairs, and they want to be able to adopt and co-parent children just like straight couples. The new bill doesn’t grant them those rights. And as long as they choose the likes of Panti to argue their case for equality, it’s difficult to see that changing.

Homosexuals insist that their nature is an inherent, essential reality, and not a lifestyle choice. But if we were to judge by the get-up and carry-on of some of those in the Pride march last week, that’s hard to believe. Some are definitely choosing to pursue a way of life that is quite alien to the majority of married heterosexual parents in this country, indeed deliberately and defiantly so. And good luck to them, and it is perfectly right and proper that they should be allowed to do so in an atmosphere of legal and social tolerance.

But many have unquestionably opted out of traditional behavioural norms and expectations, and, as the whole Gay Pride movement was designed to confirm, they want us all to know how happy they are about that. It’s a bit rich, though, to thumb your nose at traditional rituals and values and then demand that the most traditional of all — marriage — be reinvented and adapted just to suit you.

Marriage is a legal and religious union between a man and a woman. That’s a definition, in the same way as Irish stew is a dish made with lamb, spuds and turnips. You can, of course, substitute wild boar, aubergines and pilau rice, and you will have a perfectly delightful meal that will satisfy more sophisticated palates. But it won’t be Irish stew.

Change the ingredients, and you change the institution. A legal, civil and religious union between a same-sex couple may well be new and wonderful, or sacrilegious and distasteful, depending on your point of view, but it’s not a marriage.

Panti is wrong on another point — homosexuals are entirely free to marry. They just can’t marry someone of the same sex. None of us can, because, whatever the resulting union might be, marriage it ain’t. By choosing to enter a civil union with a same-sex partner, homosexuals are opting out of the traditional trajectory of courtship, marriage and procreation, but they’re not the only ones. An increasing number of heterosexual couples are also eschewing marriage, and within five years civil unions may outnumber weddings in this country.

The only legal difference between the new civil partnership and a traditional marriage relates to children. Civil partners can’t adopt; married couples can. A child raised in a same-sex household will have no maintenance claims against the partner who is neither their biological nor adoptive parent if the union breaks down. Gay campaigners see this limitation as an infringement of their rights as consenting adults. But their rights are not the only ones to be considered in the equation.

Two adults are free to choose to live in a same-sex household with the blessing of the state, if not all of the churches. In considering the best interests of a vulnerable child in need of an adoptive home, though, the state has to have regard to that child’s legitimate expectations of a placement that maximises their exposure to male and female role models, their chances of having siblings, their prospects for a rounded self-image, the likelihood of social acceptance in their crucial formative years.

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