There are only two nations where the introduction of same-sex marriage was widely celebrated as an affirmation of equality by the LGBTI community, namely Ireland and Australia. There was much less public excitement when same-sex marriage was legalised by a parliament (Britain) or legitimised by a court (US).

It may be unfashionable to say so but the person primarily ­responsible for the celebrations on Wednesday was Tony Abbott. Sure, ­Abbott was opposed to same-sex marriage when he was prime minister and played a leading role in the recent No campaign.

However, even if between September 2013 and September 2015 Abbott had favoured changing the definition of marriage, he could not have obtained support of the Liberal partyroom or the Nationals. In short, until this week, the Coalition was not ready to legislate this particular cause.

The Labor governments led by Julia Gillard and Kevin Rudd did nothing about same-sex marriage despite the fact that on this issue they enjoyed majority support in both houses, thanks to the Greens and some ­independents.

In his last months as prime minister, Abbott got the Coalition to agree to a plebiscite on the issue to be held after the 2016 election. As part of a deal in overthrowing Abbott in September 2015, Malcolm Turnbull conceded to the Liberals and Nationals that he would continue Abbott’s policy.

Hence Turnbull took a commitment to hold a plebiscite to the election in July last year. There would have been a plebiscite on February 11 this year except the relevant legislation was ­defeated in the Senate by Labor, the Greens and some crossbenchers.

So the Prime Minister, with the active backing of senior cabinet ministers Mathias Cormann and Peter Dutton (both one-time ­Abbott supporters), decided to go down the postal survey route, which did not require parliamentary approval. There was a High Court challenge on this issue, which the justices rejected by a seven to zero vote. It’s worth remembering the ­extent to which some supporters of same-sex marriage opposed Abbott’s proposed plebiscite and Turnbull’s postal survey until this week.

On Wednesday, Qantas chief executive Alan Joyce and Labor Senate leader Penny Wong featured prominently in the media coverage of Yes victory celebrations. Joyce was a vehement ­opponent of Abbott’s plebiscite proposal but lent support (including a significant personal financial contribution) to the Yes case in the postal survey.

On Wednesday, the Irish-born Joyce told a rally in Sydney the ­almost 62 per cent Yes vote was “an amazing outcome and we should all be very proud of this amazing country”. He would not have been able to make so effusive a statement if same-sex marriage had been introduced by politicians. Likewise Wong, who opposed a plebiscite and a postal survey, said “thank you Australia” immediately after the result was announced. It was a gracious statement. But she would not have been able to thank her fellow citizens if the decision had been made by her parliamentary colleagues alone.

Liberal senator Dean Smith, who has introduced a private bill on this issue, went along with his party’s policy on the plebiscite/survey in the knowledge that this was the only means by which same-sex marriage could be legislated ­before the next election.

Addressing the Senate on Thursday, Smith said: “I never ­believed the day would come when my relationship would be judged by my country to be as meaningful and valued as any other; the Australian people have proved me wrong.” Such a statement could not have been made without the affirmation of same-sex marriage by a large majority of Australians in a secret postal ballot in which 80 per cent of the electorate voted.

For its part, the No case was gracious in defeat. On Wednesday, Abbott posted a statement on Facebook that declared: “I congratulate the ‘Yes’ campaign on their achievement; the people have spoken and, of course, the parliament should respect the ­result.” He also said Australians wanted their say on this issue and “the result demonstrates that seeking their views was the right thing to do”.

That’s correct. In Ireland and in Australia a clear majority of citizens in two traditionally socially conservative nations agreed that a marriage could be other than a union between a man and a woman. The Irish got there ­because a constitutional amendment was required. Australians got there because of an Abbott ­initiative that Turnbull followed (albeit reluctantly in the first ­instance). In both instances, the people have had their say and the matter is finalised.

It so happens that the breakdown of the postal survey vote tells us a lot about contemporary Australia and, in the process, has demolished some myths.

On the ABC TV program The Drum last Monday, Adam Carrel made his inaugural appearance as a panellist. Carrel is a partner at the accounting firm EY, working in the area of climate change and sustainability services. After dismissing Abbott’s position on same-sex marriage out of hand, the EY factotum went on to say that any consideration of religious freedom on this issue “plays to the base of white Christian Australia”.

Carrel looks white. His put-down of Christianity is fashionable among the inner-city intelligentsia. But the postal survey result demonstrates that the core of opposition to same-sex marriage in Australia is not based in “white Christian Australia”.

Many of the leaders of the No case were not white, ­including Christians from Asia, the subcontinent and Africa. Moreover, the core of the No vote base was in the heavily multi­cultural areas of western Sydney, home to many Buddhists, Hindus, Sikhs and Muslims.

The strength of Abbott’s decision to allow Australians to decide on the definition of marriage is that the survey result demonstrates to all — Yes and No voters alike — that same-sex marriage had clear majority support. Only the Irish can say the same.