Open this photo in gallery For many of those younger voters – and a decent number of older ones – climate change already ranks as something very high-stakes indeed. PATRICK DOYLE/Reuters

Less than four months from election day, Justin Trudeau needs to land on a message to rally centre-left voters behind him.

Apparently, saving the planet from what his government has identified as a climate-change emergency, or at least ensuring Canada does its share on that front, does not quite qualify.

Contrary to fairly common assumptions, recent conversations with senior Liberals suggest they do not intend to make fighting climate change the centrepiece of their national campaign this fall.

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Instead, their policies and promises on that front – including the federal carbon-pricing policy, upheld last Friday by the Ontario Court of Appeal after a challenge by that province’s government, the same outcome as in Saskatchewan last month – are more likely to play a supplemental role as they return to some variation of their message from the 2015 election about supporting and growing the middle class.

It is, on its surface, a somewhat curious decision, for a progressive party in the current political moment – especially one with the Liberals’ particular political imperatives.

Their path to re-election hinges on convincing non-Conservatives who voted for them last time, but have grown disillusioned, that the stakes are too high to waste their votes on the NDP or the Greens, or decline to cast ballots at all. In particular, they need to reinvigorate younger voters who came out in unusually large numbers in 2015.

For many of those younger voters – and a decent number of older ones – climate change already ranks as something very high-stakes indeed. The summer months could make it all the more so, with wildfires, floods and deadly heatwaves providing visceral evidence to supplement researchers’ increasingly dire warnings about the need for immediate action. And the sense of urgency may also be amped up by progressive politicians elsewhere, especially those campaigning south of the border for a chance to replace Donald Trump, treating environmental policy as a much higher priority than they have previously.

The easiest explanation for why the Liberals wouldn’t make channelling such sentiments their primary focus is found in a recent, much-cited public-opinion poll suggesting that while most voters rank fighting climate change as a top priority, only about one in four are willing to pay more than about $100 a year toward that end. And that indeed might help explain why Environment Minister Catherine McKenna recently provided assurances that her party doesn’t intend to hike the carbon tax beyond a planned increase (to $50 a tonne) in 2022, despite it needing to be significantly higher to have the impact carbon-pricing advocates envision.

But it’s not as though the only way Mr. Trudeau could run a climate-focused campaign is by arguing for much higher taxes on consumption.

If he wanted, he could present the existing carbon tax not as a cure-all, but as a first step toward a sustainable future. He could emphasize, more than he has to date, other climate-related policies his government has introduced, from public-transit spending to electric-car subsidies to energy-efficiency investments. And he could package together ambitious new promises – on infrastructure, retrofitting, regulation, conservation, clean technology investment – into a promise to make Canada a leader in the new green economy.

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While there will probably be elements of all that in Mr. Trudeau’s campaign, the Liberals seem to think that treating climate change as his central mission isn’t the way back into the hearts of voters who four years ago saw him as a generational leader.

There is no way of knowing their precise calculus on that front without seeing their internal polling. But their record to date – specifically their support for expanding the Trans Mountain pipeline (and purchase of it) – is likely a big part.

In trying to elbow out the parties to their left that threaten to split their vote, the Liberals’ imperative is to suggest there’s less daylight between them and the NDP or the Greens than between them and the Conservatives. But both those parties oppose pipeline expansion and favour phasing out oil extraction altogether, which gives them the opportunity to accuse the Liberals of phoniness, hypocrisy and actually being closer to the Tories on this issue than they are to them.

Rather than spending the campaign challenging that perception, the Liberals seem more inclined to highlight promises around affordability, equality and social responsibility – such as national pharmacare, or a further expansion of child benefits – which might speak to centre-left voters’ needs and values without giving those voters as much cause to consider where Mr. Trudeau leaves them short.

If Mr. Trudeau sticks with that strategy and it pays off in another term, a de-emphasis of climate policies during the campaign would not necessarily mean the same in government. He made limited mention of carbon pricing out on the trail before the past election, after all, and it proved to be one of his signature policies in office.

Given the current rate at which urgency around climate change is mounting, it’s likely that any reasonably progressive government will be trying to make up for lost time by 2023, when the Liberals’ next four-year term would end. If only the Liberals decide that reality and their short-term electoral imperatives are aligned, we might get a better idea of what such an effort would look like, or more of an attempt to get buy-in for it now.

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