So, tweeted Conservative leader Andrew Scheer last week, it's time to "start the countdown." In just a few days, he said, he'd unveil his incredibly exciting, and much-anticipated plan – his description — to fight climate change. Let the tailgate parties begin.

It's taken a lot of work by his Conservative team, he explains, but they've done it: climate change can be effectively fought without a carbon tax.

The subtext: we'll deal with this, and it won't cost you anything. Go ahead and fill up, the way Conservative politicians did, posing for cameras, the day the Liberal government's carbon tax took effect earlier in the spring. Scheer will protect your right to burn fuel. Just vote Conservative.

As for the general agreement among economists that a revenue-neutral carbon tax that harnesses market forces is the cheapest and most efficient way to fight climate change, well, who're you going to listen to, a bunch of lib-left eggheads, or Andrew Scheer's hardworking Conservative team? More to the point, who do you WANT to listen to?

Start the countdown: June 19, A Real Plan to Protect Our Environment. <a href="https://t.co/VRZxX2eh8g">pic.twitter.com/VRZxX2eh8g</a> —@AndrewScheer

Scheer's pitch reminds me of U.S. President Donald Trump's rallies in Appalachia, where he bloviates about "beautiful, clean coal," energizing crowds of desperate people who want to believe that such a thing exists, and that their coal jobs are "coming back like never before" – which of course they're not .

Yaaah! MAGA!

But of course Scheer isn't prime minister, and unless he wins this fall, his plan is just another election promise.

The plan that matters right now is Justin Trudeau's, and it remains a model of virtue-signalling timidity.

Catherine McKenna, Trudeau's preachy climate change minister, just confirmed that the carbon tax, which currently stands at a nugatory $20 a tonne, or about four cents a litre, will stop once it reaches a piffling $50 a tonne, or about 11 cents a litre, three years from now.

Now, it is true that the law establishing the federal carbon tax is silent about any increases beyond 2022. But unless it rises far beyond $50 a tonne, it's not going to change anyone's energy consumption, which is supposed to be the whole point.

Going to 11 cents a litre amounts to about $6.60 extra to fill up a 60-litre tank. That would barely cover the price of three large double-doubles at Timmy's. For the sake of comparison, GasBuddy, at the time of writing, said the lowest price for a litre of regular in Ottawa was 107.9, and the most expensive 129.9.

That's a spread of 22 cents, or $13.20 a fillup, meaning drivers can save that much with a little research and willingness to go out of their way. The fact that some stations get away with charging far higher prices, and remain in business, speaks for itself.

No, changing habits — say, nudging people into purchasing hybrid or electric vehicles — will require infliction of incentive, at least at the pump. (The tax at the moment is revenue neutral, returned to Canadians on their tax returns, something that is happening right now. The idea is to change consumption habits without expanding government – effectively, the carbon tax is a conservative policy).

Prof. Christopher Ragan, chair of the Ecofiscal Commission, which exists to study the issue, reckons the carbon tax must rise to between $125 and $175 a tonne (between roughly 27 to 38 cents per litre of gas, or $16 to $23 for a 60-litre fillup) before Canadians will change their behaviour enough to meet the government's target of returning to a level of greenhouse gas emissions that is 30 per cent below 2005 levels by 2030.

Experts might disagree on where the tax should eventually level off, but stopping at $50 a tonne makes no sense. (Bryan Labby/CBC)

The non-partisan Parliamentary Budget Office recently pegged the necessary tax at a more moderate $102 a tonne, or about $13 for the same fillup.

In any case, experts might disagree on where the tax should eventually level off, but stopping at $50 a tonne makes no sense. McKenna was immediately and deservedly ridiculed in the media for her remarks.

The reason for them, though, was obvious: Justin Trudeau wants to be re-elected. If he does plan to keep raising the tax beyond 2022, he certainly doesn't want to say so right now. Yes, the tax is revenue neutral, but if you have to explain that during an election, you're in trouble.

"It's very hard for them," says Ragan. "This is an issue that is ultimately a long-run, intangible, faraway issue." And of course governments are elected for four years. And scientists keep noting that climate change will get worse, and the damage is irreversible.

I asked Liberal officials about the evident pusillanimity of stopping at $50 a tonne. The response was very Liberal – the equivalent of an exasperated sigh.

People must understand, they told me, that the carbon tax is just one tool among many, many others. The government has spent a lot of money on public transit, which it expects will bring down emissions. And on clean technology. And "we're thinking about how to sequester more carbon using natural climate solutions, like planting more trees … or protecting wetlands…"

Plus there are the rather confusing levies on industry that effectively exempt some of our largest polluters.

Well, maybe. Maybe some of those other measures will work. Maybe they won't. Government subsidies have an uneven record, and markets are good at circumventing regulation. But the one thing these other measures all have in common is that they are more expensive than the carbon tax, which is rebated to consumers. All those other measures grow government.

"There are all sorts of options," says Ragan. "But the carbon tax remains the cheapest and most efficient way to achieve change."

In that sense, Scheer's plan to kill the carbon tax outright, and resort solely to other measures, is not conservative at all, at least if he's serious about changing consumption habits. It's spendy, and big-government.

But that's short-term electoral politics. It takes serious political courage to go out there and promote the idea of short-term disruption for long term goals, the way Brian Mulroney did with his free-trade platform back in 1988. It's easier just to tell people what they want to hear.

And of course no one, Liberal or Conservative, wants to talk about climate-change adaptation, which is shorthand for the staggeringly expensive job of flood-proofing Canada, or who will pay the hundreds of billions it will take.

"Well," a member of Trudeau's staff told me at a social event last week, "we all will, won't we?"

It was an honest response, if maybe not intended for public consumption.

Perhaps in the 2023 election campaign, after a few more years of catastrophic floods and fires, voters will be more interested in honest, difficult answers.

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