Only this week, with the appointment of Dame Patsy Reddy as the next Governor-General, two party leaders, Metiria Turei of the Greens and Peter Dunne of United Future, advanced credible proposals for change to the next appointment in five years.
The first lesson is pace. With the benefit of hindsight, the flag referendum was conducted too quickly. If it had been conducted over two electoral cycles, not within one, it may have had better buy-in from parties of the left. That way there would have been the possibility of a Labour Prime Minister overseeing the final result.
And it would have given the public longer to assess the flag options at various stages.
The fact it was started and finished in one term - potentially delivering John Key, and only John Key, a victory - was the driving factor in Labour and the Greens opposing the referendum.
The next lesson is to have a plan.
There was no proper campaign strategy to either promote change or to respond to social pressure that successfully persuaded young people there was some "retro cool" in having someone else's flag on yours. It became acceptable to mock supporters of change.
The next lesson for politicians is to never take your political opponents for granted.
That was Key's mistake. The left will take great heart in showing that he can be beaten. Key assumed that the parties would stick to their own policies, because the Greens and Labour election policy was that they would support a referendum on the flag.
With the benefit of hindsight, the flag referendum was conducted too quickly.
He under-estimated their resentment at his encroachment in to territory they see as theirs, the epitome of which was raising social welfare benefits. The left's decision to criticise the process at every twist and turn was a de facto and decisive campaign against change.
Labour leader Andrew Little's attack on the integrity of the Flag Consideration Panel chaired by the eminent and principled Professor John Burrows showed how far they would go for a no-change result.
Labour's Grant Robertson gave a fine-sounding speech about how the flag debate should be held in concert with a wider conversation about New Zealand's constitutional arrangements. That's why he was voting against a referendum.
It was a newly invented condition. That was not part of its policy in the 2014 election. Besides which, there have been two reviews in the past 12 years on New Zealand's constitutional arrangements.
The upshot of those reviews is that New Zealanders don't want big constitutional conversations.
The best example of constitutional change was over the reform of the electoral system, which took 10 years from start to implementation in 1996.
Kiwis like incrementalism over big-bang change.
After Don Brash's Orewa speech on nationhood and racial separatism, the Prime Minister of the day, Helen Clark, asked Peter Dunne to look at New Zealand's existing constitutional arrangements.
He formed a cross-party committee, although it was boycotted by National and New Zealand First.
With the help of constitutional expert Matthew Palmer, it did a valuable stocktake on all of New Zealand's constitutional instruments and milestones.
But it went nowhere. It found that in view of the lack of consensus about what was wrong or how it could be improved, the risks of attempting reform could outweigh persisting with the status quo.
The next review on New Zealand's Constitution came courtesy of the Maori Party's confidence and supply agreement with National in 2011, chaired by Burrows and Sir Tipene O'Regan.
It reported on the "conversation" it had had with New Zealand and its main recommendation was to continue that conversation.
No matter how many constitutional reviews and conferences are held, there will never be written constitution in New Zealand except by revolution.
That would essentially require Parliament to hand the courts the power to interpret any such document - a document which would also necessarily entrench the Treaty of Waitangi.
Governments just don't willingly hand over power like that.
The biggest change New Zealand will experience is the move from a constitutional monarchy to a republic.
Many suggest that that debate won't begin until the 89-year-old head of state, the Queen, dies. Andrew Little says that will be the logical time to next discuss the flag. Lord knows how far off that will be, with her genes and the wonders of modern medicine.
The transition could begin more quickly and incrementally, however.
Dunne doesn't want to wait for the Queen to die; he wants to replace an appointed Governor-General (the Queen's Representative in New Zealand) with a popularly elected president by 2021.
Metiria Turei suggested that the next Governor-General be elected by 75 per cent of the members of Parliament.
If we combined their ideas and had a parliamentary-elected Governor-General in five years, then a popularly elected Governor-General in 10 years, it would be just a small step to convert the office to a ceremonial presidency with the same reserve powers as a Governor-General, and have a popularly elected president in 15 years.
Hey presto, we would have a republic without even having to argue about it - and hopefully the last excuse to keep someone else's flag on our own would disappear.
• Audrey Young supported the silver fern alternative in the second referendum, although it was her third choice in the first flag referendum. Red Peak was her first choice.
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