Don't crack the champagne just yet. The 'no' camp will never (ever) give up

Like a creature from a Harry Potter novel, it has morphed and moved, shimmied and shifted as the debate has progressed over the past decade. Always able to answer whatever progress there might be on the "yes" front with different arguments, different goal posts.

Ahead of Wednesday's result, a frustrated Liberal supporter of same-sex marriage lamented that if the postal survey result was an unthinkable "no", then that would be it for the "yes" campaign in Parliament for the forseeable future. But if the result was a "yes", then the "no" campaign would still have a say in what happens next.

"If people say no, then the answer's no. If they say yes, the answer is not [necessarily] yes."

The marriage equality debate has come a long way, baby, since 2004 when Parliament waved through John Howard's amendment to the Marriage Act with barely a grain of rice thrown.

Howard's change specified marriage was between "a man and a woman", adding that overseas same-sex marriages "must not be recognised as a marriage in Australia".

Senior minister Helen Coonan, who was in charge of summing up the government's case, spent hardly any time justifying the change. It was so obvious, it didn't need explanation. "In this bill the government seeks to reinforce marriage and its status as a fundamental and special institution in our society," she said simply.

Of course the debate has since become a lot more contentious. Following 2004's effort, there have been 22 federal bills attempting to make same-sex marriage law or recognise overseas same-sex marriages, not including the bill Liberal marriage equality advocate Dean Smith introduced to the Senate on Wednesday afternoon.

And as momentum has built for federal MPs to give same-sex couples the opportunity to marry, the "no" case has had to adapt to survive.

Initially, opponents argued same-sex marriage wasn't important enough to warrant parliamentary attention (the economy, jobs, national security were all much more critical). When pressed that Parliament could handle more than one issue at a time, anti-MPs would say voters weren't raising same-sex marriage with them (therefore I'm not going to lose my seat over this, therefore it doesn't exist).

As more and more polls showed most Australians supported change and more and more MPs came out in favour of marriage equality, the counter-argument began to shift. First it was bogged down in process, around the need for the Liberal partyroom to debate its position on a free vote for MPs. Then when that debate finally happened (remember the five-hour-plus marathon under Tony Abbott?), things became fixated on the need for a popular vote before anything happened in Parliament.

Once we got to the popular vote (via the convoluted postal survey compromise), the "no" camp has argued that same-sex marriage should be stopped because children need a mum and a dad. When it was pointed out that children have nothing to do with same-sex marriage (gay couples can already have kids), it was argued kids raised by gay parents are worse off than their straight-parented counterparts (this is not borne out by research – and still has nothing to do with gay marriage).

Not to be deterred by the glaring irrationality of all this, Abbott added a few more thoughts to the mix, venturing a "no" vote was actually about hitting back against political correctness and protecting freedom of speech and religion. Meanwhile, ads on TV incongruously worried about boys being told they could wear dresses to school.

Then, as it became clear many people had responded and thus it was very likely the "yes" side would win, the "no" camp shifted gears again: furiously paddling away on an alternate bill to the consensus option Smith has proposed. This bill, sponsored by Liberal liberty advocate James Paterson (who is also, confusingly, a "yes" voter), suggests so many exemptions for those who don't support same-sex marriage that it would actually increase discrimination against gay people.

It would also keep the existing Howard man-woman definition of marriage, with "the union of two people" relegated to a second-class add on – like the kiddies' table at Christmas lunch. Ambit claim or not, it demonstrates how utterly shameless the "no" side is willing to be.

While Paterson withdrew his bill hours after the clear "yes" result was announced (saying he will focus on amendments to Smith's bill instead), this will not mean "no" supporters stand graciously aside, waving a rainbow banner as gay couples walk down the aisle.

As Australian Christian Lobby managing director Lyle Shelton ominously noted after the ABS announcement, "it's important for us now to focus on the parliamentary process". Or as cabinet minister and prominent "no" spokesman Matt Canavan said, "I'm not here to sing Kumbaya and agree with everyone all the time".

Turnbull has pledged a vote in Parliament before Christmas, but his authority within the partyroom is shaky at best and the "no" camp has nothing to lose now. Indeed, history proves that as Australia gets ever closer to legalising same-sex marriage, opponents to change get wilier and more out there.

So, celebrate Wednesday's history-making, heart-filling result. But don't for a second be complacent.

It's not over yet.

Judith Ireland is a Fairfax senior writer.