On a day that started with Donald Trump, it seemed somehow fitting to end it in the company of the Australian Christian Lobby.

Last night was the launch of Stealing from a Child: the Injustice of ‘Marriage Equality’ written by Toowoomba doctor David van Gend. I went to high school in Toowoomba, which is basically a twee garden festival surrounded by right-wing religious cults. In the middle of Groom, the electorate with the second-highest vote against same-sex marriage, Toowoomba has long harboured the sort of fundamentalist religious organisations that make the Amish look like the Red Brigade. The Australian Christian Lobby’s Lyle Shelton comes from Toowoomba, and the Magnificat Meal Movement, formerly the Celtic Adorers, is situated on the rural fringe.

Shelton was there last night to hear van Gend espouse the usual grab-bag of extremist views: that same-sex marriage will change traditional marriage, that it is bad for children, that it will usurp parental say over children’s education and force children to study dangerous pro-gay gender theory (i.e. Safe Schools). He also thinks that “mother” and “father” will be removed from birth certificates and “husband” and “wife” will become “Partner 1 and 2”.

The regional doctor said that the four pillars of marriage were consent, a man and a woman, monogamy and “for life”. But even in Toowoomba, the number of marriages fitting that description would be quite low; here in the real world, you’d be the subject of a reality-TV series. Van Gend also referred to Julia Gillard’s 2013 apology to the victims of forced adoption, asking “which future prime minister will have to deliver the apology to the motherless children” of gay marriage? (He clearly hasn’t met any lesbians).

Marriage was important to “keep that feral-by-nature male with the mother of his child”, he said, which made him sound like an evolutionary biologist. This is nonsense, but it is his arguments about child-rearing are the most dangerous.

Van Gend says in the book that the science is settled, “that a child does best, on average, when raised by married biological parents. All family structures that fall short of this ideal, that disrupt a child’s kinship bonds (including divorced, blended, single-parent or same-sex parent structures) confer similar levels of disadvantage on the child.”

“We conclude that any policy that deliberately deprives of a biological parent (such as same sex ‘marriage’) is against the best interests of the child.”

The book cherry-picks various studies to prove it’s point, ignoring a meta-analysis of 33 studies published in 2010, which found that children of same-sex parents fared equally as well as other children on a range of social, educational, emotional and educational outcomes. Several subsequent studies have replicated these findings.

To a questioner he said, “Equality for two men is inequality for the child,” adding that Sir Elton John and his husband, David Furnish, had “rented a womb” to have a baby, which would “never know its mother”.

“You steal from a child when you strip away her entire moral community.”

This is the sort of propaganda that will be widely disseminated if Malcolm Turnbull goes ahead with his controversial plan to hold a plebiscite on marriage equality. Legislation to allow a plebiscite was introduced this month, but with Labor, the Greens and the Nick Xenophon Team indicating their opposition, the bill looks likely to fail in the Senate.

[‘Grassroots’ groups opposed to same-sex marriage linked to Australian Christian Lobby]

Today’s Newspoll in The Australian reported that 48% of respondents would like Parliament to vote on the issue, while 39% support a plebiscite (13% are undecided). Van Gend said that he did think that there would eventually be a plebiscite, adding that “Labor will blink after it has extracted a few concessions”.

Last night’s audience consisted of about 120 people packed into a room on the fifth floor of Sydney’s Hellenic Club (two floors above the lap-dancing club). It was the usual bunch of old, white suburbanites who had clearly come into the city to have their prejudices confirmed, although van Gend did make a point of shutting down the man who tried to equate homosexuality with paedophilia. There was a reference, however, to cultures that allow “more than one wife”, which was clearly a dog-whistle for Islam (or the Mormons.)

Stealing From a Child is published by Connor Court, the same company that publishes the books of climate change denier Ian Plimer, and it was a very similar demographic. I was the best-dressed person there (apart from the BuzzFeed reporter), and there are honestly very few places, outside my mother’s nursing home, where I can lay claim to that. If Lyle Shelton wants more followers, he’s going to need better marketing.

Greg Smith, the former NSW attorney-general, was also in the audience. Prominent in right-wing Catholic circles, the 68-year-old held the state seat of Epping for eight years after being the president of the NSW Right To Life. Ironically, he was rolled by his right-wing faction in 2014 after opposing mandatory minimum sentences and later retired from politics. His hand-picked successor, former staffer Damien Tudehope, now carries the anti-abortion torch; if the people of Epping ever want to get their rail line upgraded, they might like to cast their net a little wider.

Van Gend did actually make two statements that made sense. At the beginning, he said that “this debate about same-sex marriage seems to have been going on for a long time”. And, when putting up a slide of the word “BIGOT” graffitied on his surgery wall, he said “how bracing it is to be on the wrong side of history!”

He’s on the money there — most Australians are now fed up with the intolerable bullying of the gay community and just want the issue resolved. Continued opposition by arch conservatives like George Christensen is a bit rich, considering that he’s an unmarried 38-year-old who has seriously contemplated entering the priesthood. It’s like the road rules; if you’re going to change them, you should at least know how to drive a car.

Van Gend is a GP who also specialises in palliative care; given the average age of his audience, a book on end-of-life decisions would have been much more apposite. Euthanasia advocate Philip Nitschke is holding a seminar in Sydney next month. I bet the launch for his book, Killing Me Softly, was more fun than this one. He’s on the right side of history.