Bill Shorten doesn't appear to have a strategy for winning the debate on marriage equality

Though it didn't attract a huge amount of comment, Bill's Shorten's article for Fairfax last Thursday may turn out to be an important moment in the campaign for marriage equality – not for the outcome, which is all but assured, but for the manner in which we reach that milestone. His argument – not new, but newly prominent – is that the government's plans for a plebiscite on the issue are not just a waste of taxpayers' money but also, and more importantly, a potential catalyst for homophobia. As he put it:

I don't think enough attention has been paid to the biggest risk a plebiscite brings – the danger and the damage of unleashing a divisive, drawn-­out debate.

A plebiscite could act as a lightning rod for the very worst of the prejudice so many LGBTI Australians endure. A platform for people to attack, abuse and demean Australians on the basis of who they love.

Now, there's been a lot in the papers recently about Shorten's inability to 'land a punch' on the PM, and one can hardly blame the leader of the opposition for trying to change the angle on his opponent. But this haymaker doesn't just miss its mark; it threatens to propel our hapless challenger through a full 180 degrees and clean up the referee on the way through. By inviting the opponents of same-sex marriage to take their stand on the high ground of free speech, Shorten is in danger of changing the issue from the expansion and expression of human freedom to the deliberate restriction of the debate itself. I can think of one or two culture warriors who would like nothing more than to characterise the push for same-sex marriage as yet another example of a smug 'elite' imposing its views on 'ordinary' Australians. If Shorten persists with this line of argument, he will not only give them that opportunity; he will demonstrate that they have the ghost of a point.

Shorten's confusion is perfectly caught in his comments about the 'taboo topic' of youth suicide. He notes that when he was a young man the shame felt by many homosexuals would sometimes lead them to take their own lives; but such was the stigma attached to being gay that no one would talk about what had happened, or why. 'I often wonder if, for some, the stigma and the struggle of imagining a future, lonely, isolated, treated differently, was too much to bear', writes Shorten, adding: 'That same prospect still haunts too many young Australians who identify as gay, and it won't stop until we banish discrimination from our nation's laws and our national life.'

All of which is true, of course. But in his desire to confine the old taboos to the dustbin of Australia's history, Shorten is proposing, in effect, to set up a new one in its stead. This is a bad idea in principle and, I think, problematic in practice.

For one thing, it will give an enormous fillip to the anti-political correctness brigade, with all its attendant, self-pitying fantasies about progressive elites and anti-Christian prejudice and white being the new black etc, etc. Nor would their claim of a double standard be entirely without foundation, in such circumstances. One doesn't have to buy into, or indeed take seriously, the attempt to draw a moral equivalence between the ridicule and abuse of a despised minority and the discomfiture of social conservatives to conclude that there is no in-principle difference between silencing the latter group and telling the former one to stay in the closet. Clearly Shorten is not proposing an extension of the hate speech laws, and since free speech is a negative right – imposing on others no positive duties – no one is under any obligation to give the opponents of same-sex marriage a platform. But he is proposing to take away a debate that is, for the moment, 'on the table' (as a former PM liked to say) on the grounds that in the course of it some people might say things other people find hurtful. If you want to find out exactly how hateful some people can be on this issue (as on others), this would be the quickest way of going about it.

More important even than this, however, is the way Shorten's logic neatly circumvents the process by which we came to be where we are now. After all, it was the people who challenged the taboos the Labor leader cites in his article – who patiently educated public opinion – who are the real heroes in this debate, and their triumph is as much a victory for free speech as it is a challenge to some of its uglier manifestations. It's easy to mock the IPA types who talk about the marketplace of ideas (a phrase to which they are bonded, apparently, perhaps because it implies some occult identity between capitalism and free expression), but the fact is that the best way to defeat an argument is to call it out as unreasonable, illogical etc.

One of my few fond memories of Kevin Rudd is of him sitting on the Q&A panel, answering a question from an audience member who, in the light of Rudd's support for same-sex marriage, had challenged his right to call himself a Christian. 'Well, mate,' Rudd replied, in that folksy way he had, 'if I was going to have that view, the Bible also says that slavery is a natural condition.' Okay, he's slightly confused his testaments, but as a way to shift the onus back on to the questioner and his constituency it's not at all bad. And remember that Rudd came late to his position: not, presumably, spontaneously, as a result of some random reconfiguration of neurons, but because he'd listened to the arguments of others and decided that those in favour of marriage equality were superior to the ones against it.

It's no mystery why some of the most impressive performers in this debate are from the conservative side of politics: it's because they've made the effort to listen and, having listened, have changed their minds. No doubt some have done so for reasons of political expediency; but my sense is that most have done so sincerely, because they realise that, contra the culture warriors, same-sex marriage is not about the homosexualisation of society but the socialisation of homosexuality – about the increasing conservatism of the LGBTI community, or the desire of many people within it to feel – to be – a part of the mainstream.

If Shorten wants to say that the Australian parliament should deal with this issue now, fair enough. The idea of a representative democracy is that politicians should represent us and, if they don't, be punished at the ballot box. Plus we all know that the current policy was conceived as a sop and a stalling tactic by Malcolm Turnbull's predecessor, a far less progressive package all round if the history books are to be believed. But to argue against a plebiscite on the grounds that it might be divisive and damaging is absolutely the wrong way to go, and may even license the kind of hate speech Shorten is concerned to forestall.

If there has to be a plebiscite then supporters of same-sex marriage should regard it as an opportunity to cement their gains and further educate public opinion.