Sometime this summer, once Prime Minister Justin Trudeau calls the next election, our political leaders will try hard to lead us, like a herd of confused cattle, into a stupid fight and the wrong conversation.

Conservative leaders intend to make Trudeau's carbon tax the big issue. Conservative premiers are fighting it in court. Federal Conservative leader Andrew Scheer is promising to kill it if Canadians make him prime minister.

Basically, conservatives argue that the tax is just more wealth redistribution, and that it won't reduce emissions or have any real effect on climate change.

Liberals will argue that Canadians are big emitters, and must do their share, and they will hint that anyone who opposes the tax is a climate change denier, and they will mock Scheer's plan, if he has one. They will call their measure a "price on pollution," rather than what it is – a tax – and generally blather away about its virtuous imperative.

For the record, the Conservatives are right on just about every score. Right now, the tax increases a litre of gas by about four cents, about $2 a fill-up. That will rise to about 11 cents by 2022; or about $5.50 a fill-up. I can save more than that right now just by driving to a neighbourhood where gas is cheaper.

The carbon tax is practically nugatory, and as long as it's so puny, it won't change most people's energy consumption. (The Liberals concede that privately; they say they're at the stage of "putting the chain on the bicycle," meaning that someday, the tax might rise to a level that will convince people to buy smaller cars, or pay an extra $5,000-$10,000 for a hybrid. But not for a long time.)

Canada's aggregate emissions

To be clear, Canadians are indeed big emitters per capita, but the conservative reply to that is correct, too: our aggregate emissions are just a few percentage points of global output. Far bigger economies have made it clear they will not impose any policies that will curb their economic growth.

According to the Intact Centre for Climate Change Adaptation at the University of Waterloo, there are nearly 1,400 new coal-fired electricity plants in the works worldwide.

Centre director Blair Feltmate points to scientific consensus: the climate change that has happened so far is irreversible, and "even if we were to go to zero emissions tomorrow, the effects will continue to get worse. And we are not going to zero emissions. The world will continue to use 30 per cent oil, 30 per cent coal-fired electricity, and 30 per cent natural gas. We can't meet even modest goals."

"The carbon tax in Canada right now is symbolic," says Feltmate. "In fact, there is a danger in it: that it will allow liberals to say they've done their part, and carry on the way everyone does."

The tax also provides an excellent diversion to keep the public's attention away from something our politicians are not saying a word about: the monumental cost of preventing, or paying for, the damage climate change will deliver from now on.

Entire neighbourhoods will have to be evacuated in the next few years. Others will find themselves on newly redrawn flood plain maps. (Michel Aspirot/Radio-Canada)

Canada needs to be flood-proofed, and somebody has to pay for it. Yes, there are other threats, too – fire, hail, wind, snow load, permafrost loss and shoreline erosion will all cost a great deal of money to remediate – but flooding is the big, urgent one.

Entire neighbourhoods will have to be evacuated in the next few years. Others will find themselves on newly redrawn flood plain maps, forced to pay both individually and at the community level for some awfully expensive flood-proofing measures. Even those on higher ground will have to cope with increasingly frequent "waterbomb" storms that park over a city and dump millions of gallons of water in a single rainfall.

Double sump pumps, flood alarms, re-grading, waterproof windows at ground level, backflow valves, diversion channels, underground cisterns, concrete barriers, berms, improved natural drainage infrastructure, better storm sewers — all of those things will need to be done if at-risk homes and communities are going to keep their market value. Or, put another way, if homeowners want to safeguard the biggest investment they have.

Paying some piddling carbon tax on a fuel fill-up is going to have precisely no effect.

Eventually, and rather quickly, I suspect, the question will become who is going to pay for all these crucial prophylactic measures. No one knows how much money flood-proofing Canada will cost, but it's safe to assume hundreds of billions of dollars. And experts like Feltmate have already calculated that NOT doing the floodproofing work increases the eventual cost by 400 to a thousand per cent.

The conservative answer to the who-will-pay question, particularly at the level of the individual homeowner, is obvious: Caveat emptor. If you made the choice to buy near a river or on low land, you own the consequences. To paraphrase the rallying call of the Tea Party, founded in 2008 in answer to government bailout plans for subprime homeowners, why should I pay for my neighbour's bad choices?

There is a certain logic in that, but it doesn't apply to what is coming. Many of the homes that will be identified as at-risk when the federal government's new, updated flood plain maps start coming out next year were not believed to have been on flood plains when they were built.

And, as Feltmate points out, the maps will likely have to be re-updated in another 10 years.

It's also pretty clear that as climate change worsens, everybody – everybody — will need basic defences such as sump pumps and backflow valves, which will cost thousands to install. (Yes, some municipalities have programs to help pay for installation, but they tend to ensure claims are so complex and time consuming as to discourage most applicants; Toronto, says Feltmate, has only a six per cent uptake for its subsidy).

And conservative allergy to government assistance usually only extends to other people's problems.

Paying for flood-proofing

Just as there are no atheists in foxholes, rugged individualism tends to disappear when you're up to your waist in basement water.

And in any case, let's not forget where we live. This is Canada, for heaven's sake. The cost of flood-proofing this country will be largely paid for with tax revenue. It's inevitable.

It is a clear and present danger at this point, and what are we discussing? A meaningless bit of window-dressing sin tax that would barely cover the cost of morning coffee once a week for most drivers, and is largely being rebated to taxpayers through the income tax system (it is revenue neutral) rather than put toward, say, digging diversion channels or building barriers or strengthening sewer systems, etc.

Our political leaders, presumably, know all this. If they don't, they bloody well should. And in any case, they aren't talking about the cost of remediating damage. (A Liberal acquaintance says he's pretty sure Trudeau addressed it in a debate several years ago, but said I'd have to check).

The carbon tax debate is misdirection. Rather than posing at gas stations filling up their vehicles, Conservative politicians could pose outside homes right here in Ottawa filled with filthy river water. And perhaps Liberals could show a little courage and start talking about protecting the country, rather than fiddling with bicycle chains.

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