The French constitutional council may have blocked the president’s carbon tax for the wrong reasons late last night, but the message France unintentionally relayed about emissions-curbing taxes is still worth noting, especially as the United States may consider similar ones.

In an eleventh-hour decision, the court ruled the 17-euros charge for each ton of carbon emissions violated “the principle of tax equality” because it excluded 93 percent of industrial emissions.

Notably, exemptions would have been extended to the core of French industry, including power plants, steel factories, airlines, and public transportation. These very industries helped the great Charles de Gaulle restore France as a functional world power. They also helped him mitigate the appeal of communism. So crucial have these industries been to French standing that it is no wonder they were completely or partially excluded from the planned emissions tax.

The council’s decision is even more notable considering just who Sarkozy’s taxes would have hit: the average French citizen. The most taxed items would have been gasoline and heating fuel. To allay what certainly would have been inevitable popular angst, Nicolas Sarkozy intended to offer tax reductions or “green cheques” to low-income families.

Now, members of Sarkozy’s party have put themselves in an awkward position as they rework the proposal for mid-January. If they pursue the same measures but with more equal application, they will burden essential industries; and if they don’t harangue industry, their emissions efforts will be feebler — especially embarrassing in the context of France’s pre-Copenhagen posturing.

But de Gaulle would caution Sarkozy and his followers that a weakened industrial sector means a weakened France. And as the United States considers similar measures, lawmakers should remember that principle doesn’t apply to France alone.