Jacinda Ardern is the first MMP prime minister prepared to publicly humiliate herself in the interests of her Government's support partners.
The convention since 1996 has been that policy differences are sorted behind closed doors, with prime ministers then maintaining a fiction that a consensus has been achieved.
It hasn't worked for anyone, big parties or small.
Back in 1996, when Jim Bolger agreed to Winston Peters' ill-fated referendum on compulsory retirement savings, Bolger and most of his National Party ministers publicly backed the proposal.
The main exception was Jenny Shipley, then focused on taking Bolger's job.
Instead of being a triumph for NZ First over National's quarter-century of hostility to such a scheme, the referendum became about the people versus the establishment.
Bolger and Peters were humiliated with 92 per cent voting against them. Within months, Shipley overthrew Bolger, Peters was sacked, the coalition collapsed and Helen Clark became New Zealand's second woman prime minister in coalition with Jim Anderton's Alliance.
In retrospect, how might history have unfolded if Bolger, National and the bureaucracy had publicly opposed the scheme — allowing Peters to pitch his big idea as the people speaking common sense to power?
Similarly, with the benefit of hindsight, would it have mattered had Clark and Anderton taken different public positions on behalf of their parties on Afghanistan?
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Is there any reason Clark couldn't have rubbished Peters' SuperGold Card rort but said it was a condition for her third term?
John Key's National lasted longest maintaining a veneer of unanimity with Act, the Māori Party and UnitedFuture but it didn't work out for the minnows.
Might National now have viable coalition partners if Key had positioned Whānau Ora not as a good idea, but as an abhorrent race-based programme that National opposed but which it had been forced to implement thanks to the brinksmanship of Tariana Turia and Pita Sharples?
Would Act now be doing better if National had not decided charter schools were a good idea after all, but publicly opposed them?
It doesn't matter that in none of these hypotheticals would the players have been telling the truth.
Similarly with Ardern's positioning on the capital gains tax (CGT). It is complete nonsense that she was unable to pursue the CGT because of Peters' opposition. The CGT was never scheduled to come into effect until 2021/22 and there is absolutely no reason it needed to be legislated for now.
Ardern was perfectly able to say the current Coalition could not agree on a CGT but that Labour would campaign for it in 2020, and let the chips fall where they may. She could then have legislated for it in late 2020 for implementation in 2021/22 as planned.
In the meantime, the implementation work within the IRD that Grant Robertson had underway could have continued.
Instead, Ardern has successfully allowed NZ First to go around the country as the saviour of the farmer, small-business owner and landlord, while the Greens can rightly claim to be the only party for those who support a CGT. Both are back on track to get over 5 per cent. Even if that is at Labour's expense, it will secure Ardern a second term.
Ardern is the undisputed champion of political PR, so we should assume this was all planned. It speaks to her character that she has been prepared to accept the temporary personal humiliation to prolong her Government in a way Key, Clark or Bolger never would.
Still, no prime minister can tolerate too much humiliation, both personally and because it would ultimately drain all public confidence in their Government.
That is a problem for Ardern because, on all substantial matters, her Government is a failure for reasons that barely need reciting, including KiwiBuild, child poverty, mental health and teacher strikes.
Luckily for Ardern, Shane Jones and Labour favourite Wayne Brown have come to the rescue with the Upper North Island Supply Chain Strategy Interim Report.
The report outlines a pathway for resolving the vexed port location issue, which is becoming ever more urgent. It lays the groundwork for Auckland's used-car and container port to leave the CBD while improving its cruise-ship terminal.
The remaining land would be progressively developed to surpass Sydney and the other most beautiful waterfront cities in the world, boosting Auckland's attractiveness for its citizens and tourists.
Nothing would do more to resolve Auckland's transport disaster while supplying 77 hectares for public amenities and high-value apartments and retail. The removal of Auckland Council's implicit subsidy of the port could only improve the Super City's financial position.
Arguably more important is what the proposal would do for Northland, one of the most impoverished parts of New Zealand. That depends on proper world-class rail and road links between Auckland and Marsden Point, which would also have the effect of turning Whangārei into part of a megalopolis including Auckland, Hamilton and the Bay of Plenty.
This is a project that can bind together Labour and NZ First — Auckland and Northland — for the foreseeable future. Taking at least 20 years, it would cause no job losses or economic disruption in the short run but it would give Ardern's Government a legacy to be proud of, and one she could preside over for what now looks like being an extended term as prime minister.
In 100 years, no one will remember KiwiBuild let alone slushy machines. But they will remember what Ardern and Peters did for Auckland, Whangārei and, by extension, the rest of New Zealand by picking up Jones' and Brown's process for reform.
- Matthew Hooton is managing director of PR and corporate affairs firm Exceltium.