Rioting in the streets is the sword of Damocles hanging over every decision a politician makes—especially when those streets happen to be French.
And rioting in the streets is what put an end to a new gas-tax proposal in France this week.
Technically, its wasn't even a straight gas tax.
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The French government proposed to tax carbon, which would have added about 15 cents a gallon to the price of gasoline, or a little less than 3 percent, starting Jan. 1.
It may not sound like much, but the proposal filled the streets with protesters in yellow jackets for three weeks. The protesters smashed windows, blocked roads, overturned and torched cars, and defaced public monuments in an effort to get the higher gas taxes reversed.
French President Emmanuel Macron
The protests prevailed on French President Emmanuel Macron, who campaigned on a platform of setting an example for the world in cutting greenhouse gases, to postpone implementation of the carbon tax proposal for six months.
Polling showed that 70 percent of French residents opposed the measure, even after they elected Macron in a landslide last year.
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Prime Minister Édouardo Phillipe announced the decision to postpone the measure Tuesday, just as world leaders began meeting in Katowice, Poland, to discuss the next steps for implementing the Paris Climate Accords.
Economists frequently note that fuel taxes or carbon taxes are more elegant solutions than fuel-economy mandates to promote better fuel efficiency and cleaner air.
In the U.S. many fans of electric and fuel-efficient cars, along with quite a few executives in the mainstream auto industry, have long been critical of Congress for pushing fuel economy mandates onto automakers, rather than providing incentives for consumers to buy greener cars with a gas or carbon tax.
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They invariably run into mass protests, however, because they take an immediate bite out of almost all consumers' pocketbooks, while those consumers see no immediate benefit.
Gas taxes are also considered regressive, falling more heavily on lower-paid working people who often have to drive more to get to their jobs than those who are better off.
When those consumers feel the pain, they take to the streets—more reliably in response to higher fuel or food prices than perhaps any other influence.