For a few months in 2013, the figure of 6.9 million took over the national consciousness.
A projection of what the population could grow to by 2030, the number eclipsed the White Paper it was a part of and became a motif for the Government's critics.
Coming after a clear electoral signal from Singaporeans that the population had grown too fast for their comfort, "6.9 million" became, for them, a symbol for how out-of-touch the People's Action Party seemed at the time.
In the two years since, the Population White Paper has disappeared from governmental mention , and so effectively that it sometimes seems like the entire episode was a fever dream.
But that the population conundrum is still the one issue with the power to swing votes across the board was made clear by an unscheduled prime-time interview with Prime Minister Lee Hsien Loong that was aired last weekend. Billed as A Conversation With The Prime Minister, PM Lee spent a large chunk of the interview, conducted by former ambassador Chan Heng Chee, discussing the difficulties of managing the population.
The interview was not an episode in an ongoing series, or an occasion to address any important breaking news, and it was hastily turned around: filmed on Friday and aired on Sunday.
It was about giving Singaporeans a sense of comfort that their leaders would not charge ahead without their buy-in, nor refuse to pull back from a path the people objected to - all in the name of their "best interests".
To all intents and purposes, it was a chance for the country's leader to speak to the electorate at the start of what looks to be a quick election season. The aim was likely to get out the message before the sound and fury of opposition parties at the hustings.
On that front, his message was not new, but the way he delivered it was. Gone are the days of party leaders cautioning Singaporeans - imaginary finger wagging - that the country will go extinct if it does not accept substantial immigration. Gone are the days of implying that emotions and sentiments are less real or important than hard indicators or economic requirements.
Rather, PM Lee's message was aimed squarely at the heart, apparent in the way he responded to three facets of the population conundrum.
First, he did not try to refute the view that foreign immigrants have taken jobs from locals or pulled down wages in all socio-economic sectors. In the past, party leaders pointed to employment or wage growth statistics, contrasting them to those of other countries, to debunk these charges.
Instead, in a perhaps delayed recognition that winning the argument is not the same as convincing your audience,
he said simply that he understood the sentiment, and that the Government wants to protect workers of all segments who cannot easily move out of their fields.
Second, he pushed back against the view that the Government has been populist in curbing the growth of the foreign workforce in the last five years.
It has indeed acted swiftly and decisively in tightening the tap on foreign labour in every sector, with the overall pace of growth down to 34,000 last year, a massive drop from 80,000 in 2011 and 144,500 in 2007.
In sectors like manufacturing, the foreign workforce has actually shrunk. And senior politicians have made clear that the foreign workforce will not go beyond one-third of the labour force, the level it is currently at.
In essence, the foreign workforce will now grow only in proportion to the local workforce. It is important here to note the nuance of PM Lee's response to the populism question.
Instead of denying that the Government had been populist, he challenged the traditional definition of populism, arguing that it was "taking cognisance" of the emotional reaction that Singaporeans have had to an intense influx of foreigners, and the way they can change the tone of society .
"Emotional or sentimental reactions" as he described them, are "real problems" - and it is not populist to address them.
This is a crossing-the-Rubicon moment for a ruling party that had, for some reason, made "populism" into a dirty word. Giving the people what they want, rather than what they need, goes against traditional PAP thinking.
An earlier iteration of government communication would have suggested that Singaporeans should be harder and hungrier than to give in to demons like emotions and sentiments.
But populism is not always weakness; it can be a sign of a responsive government, humble enough not to always assume it knows better than its people and must save them from themselves.
Third, PM Lee unexpectedly made the entire thing personal. Pointedly using the pronoun "I" throughout, he beseeched Singaporeans to understand that there are no easy choices in population management, and that he made tough choices on their behalf because he felt a responsibility towards them.
"You may agree with it, you may not agree with it, but I can tell you in complete honesty that I am trying my best to do this on your behalf. And I cannot avoid doing this because otherwise, I think I will be letting you down."
This point, that all that the Government does is with Singaporeans' best interests at heart, has been made before.
But here, it is combined with an honest acknowledgement that Singapore's leaders do not necessarily know best - they are but trying their best, to identify the least-worst option from a variety of unfortunate ones.
The "We know best" message of an earlier era has given way to "We are trying our best".
In an era of complicated and unpredictable policymaking, the former can never be true all the time, while the latter can at least form the foundation of trust, goodwill, and - when the need arises, as it will - forbearance towards policy mistakes.
This is the right note to strike, not just for the PAP's political fortunes, but for the country as a whole, whose future hinges more decisively on consensus, cohesion and a trust in its leaders than it does on taking in foreigners.
Already, the economy's current moribund performance is setting nerves on edge.
That the curbs on foreign labour are tamping growth down is evident, but whether this is the wilderness before the clearing, or a sign that we took the wrong path, is in dispute.
Are these the birth pangs of a restructured, productive economy less reliant on cheap foreign labour?
Or have we simply gone too far too fast, putting misplaced faith in the hope that Singapore companies can fundamentally change if they were forced to?
These are questions that neither economists nor policymakers can answer with absolute certainty at this juncture.
We are in uncharted territory now, and it is all a judgment call.
Population management will always be the hardest thing that Singapore has to deal with, and the biggest obstacle in the way of its continued success.
There is no solution, only, as PM Lee described it, a "mix of evils" at any one point along the spectrum from openness to protectionism.
But for all the negatives that the Republic's unique situation poses - its lack of hinterland, low birth rate and ageing population - it has an array of positives, like its fundamentally open, multiracial and multilingual character.
For Singapore's population problem was and is not about xenophobia, unlike most other developed countries.
This is the kind of society where two out of ten marry someone of a different race and three out of ten marry foreigners.
The conundrum was never about persuading a resistant population to accept foreigners for the sake of economic growth.
It was about giving Singaporeans a sense of comfort that their
leaders would not charge ahead without their buy-in, nor refuse to pull back from a path the people objected to - all in the name of their "best interests".
This shift from "Government knows best" to "Government is trying its best" should not only be in the rhetoric for the election season.
If it is one of substance, this evolution could win votes for the next generation, not just for the next general election.
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Will the population debate feature in the next GE? http://str.sg/ZnG8