I am a republican. In 1999, I voted “yes” to the proposal that the Constitution be altered “to establish the Commonwealth of Australia with the Queen and Governor-General being replaced by a President appointed by a two-thirds majority of the members of the Commonwealth Parliament”.

Even so, I agree with Malcolm Turnbull that it would be unwise to reintroduce a referendum for a republic during the time of Elizabeth II. Perhaps not even after, depending on the length of the Queen’s reign.

On Australia Day, the Prime Minister said: “I’ve led a ‘yes’ case for a republic into a heroic defeat once; I’ve got no desire to do so again.”

He has a point. The fact is that a constitutional amendment, once defeated, often goes down by a greater margin if it is proposed again without a significant change in circumstances.

Take, for example, the proposal to introduce simultaneous elections for the House of Representatives and the Senate. In May 1977, this was put to a referendum by Malcolm Fraser’s Coalition government. It obtained a total “yes” vote of 62 per cent, but did not obtain a majority vote in the necessary majority of four states. Queensland, Western Australia and Tasmania voted “no”.

A similar proposal introduced by Bob Hawke’s Labor government in December 1984, obtained an overall majority of 50.7 per cent, but only received majority support in two states (NSW and Victoria). In other words, there was a substantial decline in support for this proposal in less than a decade. A similar phenomenon with the conscription plebiscites in 1916 and 1917.

In view of the split in the republican movement in 1999 — between those who wanted minimalist change to the Constitution and those who would only vote “yes” if a directly elected president were on offer — Turnbull and his backers in the Australian Republican Movement did relatively well. After all, the overall “yes” vote was 45.1 per cent, with 54.9 per cent voting “no”.

However, the “yes” vote outside of NSW, Victoria and the ACT was quite low. The figures speak for themselves — 37.4 per cent in Queensland, 43.6 per cent in South Australia, 41.5 per cent in Western Australia and 40.4 per cent in Tasmania. To win a second referendum on the republic, the “yes” vote would need to be increased to a majority in NSW and Victoria and two of the remaining states would have to vote “yes”. It would be quite a task.

Last Monday, ARM chairman Peter FitzSimons welcomed the decision of all state premiers (except Colin Barnett in Western Australia) and both territory chief ministers to support an Australian head of state in the short term. FitzSimons delivered the following message to the Prime Minister: “You want a majority of people in the majority of states. Sir, there it is; you’ve got the support.”

The problem is that it is not at all clear whether political leaders at the commonwealth, state or territory levels can get Australians to change the Constitution. No constitutional amendment has succeeded since 1977, when Opposition Leader Bill Shorten was just 10 years old.

South Australian Premier Jay Weatherill said on Monday that the republic “goes to your ambition, it goes to our sense of pride in a nation”. The problem with this analysis is that it implies that contemporary Australia, as a constitutional monarchy, lacks ambition and pride. This is manifestly false and overlooks the fact that Australia becoming a republic would be merely a symbolic change, albeit one worth making.

The fact is that the president of a republic in the future could make the same decision as the governor-general four decades ago if the Senate blocked supply and the prime minister was intent on governing without it.

In her recently published The Dismissal Dossier (MUP, 2015), Dr Jenny Hocking argues that the palace “was complicit” in John Kerr’s decision to dismiss Gough Whitlam. Yet the evidence suggests that Buckingham Palace was surprised by Kerr’s action and not overly happy about the Queen’s representative in Australia having become involved in a constitutional dispute.

The debate about whether Elizabeth II should remain Australia’s head of state turns on symbolism. Symbols matter but they are not essential to a functioning independent democracy.

A problem for the republican cause today is that the world has changed since 1999. The attacks by radical Islamists on the West since 2001 have led to a situation in which many Australians focus more than previously on what they have in common with such constitutional monarchies as Britain, Canada and New Zealand. Moreover, the advent of the young royals, in particular, the Duke and Duchess of Cambridge, has a certain attraction to Australians of all ages.

The worst outcome for republicans in Australia would be to experience another referendum defeat along the lines of 1999. The Prime Minister, fortunately, understands this.