I suspect that’s because nobody quite knows what’s going on.
The dynamic has changed radically since pre-pandemic days. There is now a shortage of workers all over the developed world.
Skilled migrants are in hot demand.
Some of it is pandemic-related. Closing down the global flow of people for two years, and then opening up again, created huge pent-up demand.
But it has coincided with an enormous demographic shift that was always coming to the developed world.
The baby boomers are retiring and birth rates have plunged. Natural population growth isn’t going to provide the workers we need to keep our economies growing.
Immigration, at some level, is the only option.
(Ok, one other option might be a greenie-style, zero-growth economy but that’s really a whole other debate.)
Anyway, the issue, which I’ve always felt was too nuanced for populist tub-thumping, is now so complex that our politicians aren’t sure how to play it.
National has to work out where to land on this given it has only just finished complaining about Labour’s failure to attract migrants.
Labour - for all its talk about smarter, more nuanced policy settings - looks suspiciously like it might be happy to ride the economic bump the new migrants will bring into the election - John Key style.
Can they get away with that level of hypocrisy? Maybe, if the housing market gets a bounce.
On brand, Winston Peters had a bit of a crack on Friday, with a press release that raised concerns about New Zealand’s failure to align policy with planning for infrastructure and housing.
But he is a notable lone political voice and the rhetoric was pretty subdued by his own standards.
He has a point.
Six months ago we were all beating up on the Government for moving too slowly to open the borders.
Business groups were bemoaning the impact on the labour market and low net migration was copping the blame for New Zealand running higher inflation than Australia.
Some politicians and business leaders went as far as to predict New Zealand’s reputation as a destination for migrants was in tatters.
They couldn’t have been more wrong.
If the numbers stay roughly at the levels we currently see, New Zealand’s population will grow by more this year than it ever has before.
The surge in migrant arrivals this year has made an absolute mockery of suggestions that this country’s reputation was in some way “trashed” by our strong pandemic response.
The net gain - long-term arrivals minus departures - has us on track to grow the population by 100,000 this year.
It might not stay that high. Treasury and the Reserve Bank both expect the spike of the past five months to ease and annual net migration to settle around 66,000.
Economists, such as Michael Gordon at Westpac, think that is too conservative.
Perhaps the final number will land somewhere between.
Either way, it will be at historically high levels and it will certainly be the fastest and most dramatic turnaround in numbers we’ve ever seen.
It’s probably the biggest variable in forecasting the economic outlook.
What does population growth at these levels mean for inflation?
Nobody really knows. Presumably, it eases labour market demand and takes a bit of pressure out of wage inflation.
But more population means more overall demand in the economy. Migrants have to eat and live and commute.
And hopefully, if we’re doing this fairly, they also get to enjoy Kiwi life and get out for a bite to eat and a drink sometimes.
So a sudden surge in net migration throws up the perennial questions about keeping up with infrastructure investment and housing supply.
What are the social implications of this kind of growth? Where are new migrants settling, and what skills are they bringing? Are they aligned with the skills we need to boost productivity or are they workers that some industries prefer to import because they won’t pay locals enough to do the work?
There are ethical issues to consider - the kind that usually get lost in the economic debate.
Are new migrants - who are often vulnerable to exploitation - being treated fairly?
Immigration has never been an issue that divides neatly along left-right political lines.
Conservatives on the Left and Right worry about rapid cultural change, but business groups demand workers.
The liberal left tends to be in favour of open immigration policies.
But with huge demand for skilled migrant workers building through the developed world, where does that leave the poor struggling nations we’re sourcing people from?
In the next decade, demand from the US, UK, Canada, Australia and New Zealand will bring huge opportunities for skilled workers in poor countries.
But consider the effort and resources that go into training a doctor, teacher or engineer in a developing nation.
It could be devastating for the countries they leave behind.
New Zealand needs migration.
It needs to find an optimal and sustainable level. That’s probably something closer to 1 per cent annual population growth, rather than the 2 per cent we’re tracking at now.
On a policy level, it is a fiendishly difficult thing to adjust with any subtlety.
Even small tweaks can have huge implications for the migrants who are putting themselves through life-changing upheaval to come here.
That final point needs to be remembered as we have this debate. Migrants are people, not just numbers.