What would I have said if I had been called on to reflect upon the question?

I would have begun by noting that Queen Elizabeth, the head of state of Great Britain and Northern Ireland, Australia and more than a dozen other countries, would shortly be replaced by her son, Prince Charles, who would become King Charles, the new head of state of all these countries. That is how the hereditary principle works.

I would then have reflected that for much of the modern history of the monarchy/republic debate in Australia Queen Elizabeth had been central. It was generally agreed that her presence as monarch added 5-10 per cent to the NO vote to retain the monarchy when the 1999 referendum was held. Public opinion polls supported this view whenever they asked respondents how they would vote if Charles rather than Elizabeth was the monarch.

It was also argued that it would be inappropriate, even disrespectful, to become a republic while Queen Elizabeth remained on the throne. Prominent republicans, such as Bob Hawke and eventually Malcolm Turnbull after the 1999 referendum was defeated, argued that Australia should become a republic only after Elizabeth's death. Turnbull famously said in 2017, after becoming Prime Minister, that "Most Australian republicans are Elizabethans as well".

This notion took hold, making the task of those arguing for a timetable of Australia's own choosing, like the Australian Republic Movement, more difficult. This was so even though the idea of waiting was always flawed and impractical. There was no evidence that the Queen was offended; she and other members of the royal family always said that becoming a republic was a matter for Australians themselves.

A new monarch, like Charles, might be more offended. Monarchists would still argue against a republic for Australia and would claim that the new king should be given a chance before a referendum was held. Preparations for a referendum, including community consultation, would take some time anyway so another referendum would be unlikely to be held for some time after the Queen's death.

Given that scenario, "what now for the republic?". Well, the dynamic would clearly change and one of the threads tying Australia to the British monarchy would have been removed. But several other threads remain. The case would still have to be made and doing so sensitively under a new monarch would not be easy.

The invitation last week came at a time when the monarchy is clearly in an era of change. Queen Elizabeth is adjusting her schedule to take account of her age (95) and health. She has recently lost her husband, the Duke of Edinburgh, who died at the age of 99. She has delegated many roles and no longer undertakes royal tours abroad. Charles, soon to turn 73, is the immediate heir apparent.

For his part Charles, a committed environmentalist, has been outspoken in the lead up to COP26. Prior to Scott Morrison announcing that he would attend the UN climate change summit, Charles expressed dismay that Morrison and some other world leaders would not attend.

Yet the case for a republic in Australia does not depend on the character and views of the British monarch. It stands, first, on the incompatibility of hereditary monarchy with modern democratic values, and second, on the incompatibility of the British monarchy with an independent Australia. Only the first of these arguments applies in Britain itself, while both apply in Australia. Whenever, as an ARM leader, I pointed this out to the British press during a royal tour of Australia they had no easy comeback. I sympathised with British republicans who only had one string to their bow.

These dual arguments remain as strong as ever. They are the basis for the most recent example of a Commonwealth country, Barbados, moving away from the British monarchy to become an independent republic. The decision was taken by a two-thirds majority of both houses of parliament to become a republic with a Barbadian citizen as head of state by November 30, 2021. Incumbent Governor-General Dame Sandra Mason will take office as the first president, jointly nominated by the prime minister and the leader of the opposition.

I would also have written that it is not inevitable that Australia becomes a republic. It never has been, despite some Australians believing it. Anyone who still thinks so should read the recent book by La Trobe University Professor Dennis Altman: God Save the Queen: The Strange Persistence of Monarchies. Altman, a republican who voted Yes in 1999 and would do so again if a second referendum was held in Australia, cautions republicans against dismissing monarchies too lightly. Some monarchies have persisted against the odds and republicans should try to understand why this has happened.

If their persistence in parts of Europe and Asia is strange then the strangest cases of all are those countries, such as Australia, Canada and New Zealand, which have persisted with monarchy despite not having one of their own. It is in such countries, which have emerged from colonialism to full independent statehood, that the case for a republic is strongest and the persistence of a foreign monarch as head of state is strangest.