Should Stephane Dion and his fellow Liberal MPs ever find their courage, they will vote with the other opposition parties in Parliament, they will topple the Conservative minority and they will trigger a general election.

Should that happen, the Liberals will cloak themselves in green and run as the party committed to saving the planet from catastrophic climate change.

Dion revealed his intentions when he spoke to the Canadian Club of Toronto in mid-May. During a lunch-time address, he sketched the broad outlines of what he called "a vision for a richer, fairer, greener Canada," which would reconcile economic growth and environmental protection.

And he made it sound simple. All we need to do, according to Dion, is lower taxes on incomes, innovation, savings and investment - those things that give us a competitive advantage. We raise taxes on those things that are contributing to environmental degradation - pollution, greenhouse gas emissions, smog and waste.

This will also involve getting tough with wrongdoers. "We need to make polluters pay, and put every single penny back in the hands of Canadians through the right tax cuts," Dion said. "The polluters will pay - all Canadians will gain."

Upon hearing this, many will undoubtedly envision a Liberal government cracking down on the mammoth oilsands projects in northeastern Alberta, or coal-fired generating plants or smokestack industries of Eastern Canada.

Myself, I think of McDonald's Restaurants of Canada. There are more than 1,400 McDonald's restaurants in this country and they serve millions of meals every day. Roughly two-thirds of the company's sales occur at drive-through windows.

That means hundreds of thousands of motorists are sitting in their vehicles at all hours of the day, engines idling and spewing out greenhouse gases, while they wait for their Big Macs and Quarter Pounders.

McDonald's isn't the only offender. There are nearly 2,800 Tim Hortons restaurants in this country and long lineups are a routine sight at their drive-through windows. Almost every other fast food chain in the country offers the same service.

Drive-throughs illustrate the fundamental fallacy at the heart of Dion's vision. You cannot distinguish between the polluters and the Canadian public. They are one and the same. Our lifestyles are causing environmental degradation.

Any politician who would rescue the environment must either convince us to change our lifestyles or they must coerce us. Dion and Liberals clearly believe that persuasion won't work so they will use coercion.

They would, if elected, bring in a raft of carbon taxes. They have not said what they would tax or by how much, but even in the absence of such details this policy can best be described as a day late and a dollar short.

The marketplace is already penalizing Canadians for their reliance on fossil fuels. The very week that Dion was announcing his plans for carbon taxes, gasoline prices hit a record of $1.29 per litre, on average, in major Canadian cities and the Calgary-based consulting firm MJ Irvin & Associates predicts that they could hit $1.40 in the next few months.

Air Canada has begun slapping surcharges on its flights to help cope with fuel bills that hit $715 million in the first quarter of the year, up by $130 million over the same three months of 2007.

The Canadian tourism industry is forecasting a four-per-cent drop in travel this summer because of rising fuel prices and the cost of heating your home by natural gas is expected to increase, in Ontario at least, by about 20 per cent per year starting July 1.

This sort of seismic shift in economics has already had a telling effect. Cars buyers in this country are abandoning big vehicles and stampeding into small ones. In the first four months of the year, the five top-selling cars in Canada were all compacts or subcompacts - the Honda Civic, Toyota Corolla, Mazda 3, Toyota Yaris and Chevrolet Cobalt, in that order.

Sales of compacts and sub-compacts reached 182,111, or 63 per cent of total passenger car sales of 288,835. By comparison, sport utility sales stood at 8,379 or 2.9 per cent of the total.

If fuel prices continue to rise, and most experts predict that they will, all but the wealthiest Canadians will be modifying their behaviour and reducing their consumption in others ways not yet apparent. Heaping carbon taxes on top of the price hikes at the pumps and elsewhere and will do nothing but annoy.

Like every good politician, Dion will try to sell his plan as painless. New taxes on consumption of fossil fuels will be offset by reductions in other forms of taxation. The Liberal approach will be revenue-neutral, they say.

When I hear that, it reminds me that income tax was introduced during the First World War and it was supposed to be a temporary measure to support the war effort. In other words, when you hear the term revenue neutral, don't believe it.

(D'Arcy Jenish can be reached at jenish@businessedge.ca)