Senate Majority Leader Mitch McConnell (R-Ky.). (Andrew Harrer/Bloomberg)
Editorial Page Editor

To understand how dangerously extreme the Republican Party has become on climate change, compare its stance to that of ExxonMobil.

No one would confuse the oil and gas giant with the Sierra Club. But if you visit Exxon’s website, you will find that the company believes climate change is real, that governments should take action to combat it and that the most sensible action would be a revenue-neutral tax on carbon — in other words, a tax on oil, gas and coal, with the proceeds returned to taxpayers for them to spend as they choose.

With no government action, Exxon experts told us during a visit to The Post last week, average temperatures are likely to rise by a catastrophic (my word, not theirs) 5 degrees Celsius, with rises of 6, 7 or even more quite possible.

“A properly designed carbon tax can be predictable, transparent, and comparatively simple to understand and implement,”Exxon says in a position paper titled “Engaging on climate change.”

None of this is radical. Officials negotiating a climate agreement right now in Paris would take it as self-evident. Republican leaders in the 1980s and 1990s would have raised no objection.

Understand decades of climate change negotiations and what's at stake in Paris in two minutes. ( Gillian Brockell / The Washington Post)

But to today’s Republicans, ExxonMobil’s moderate, self-evident views are akin to heresy. Donald Trump, the leading GOP presidential candidate, says, “I don’t believe in climate change.”Sen. Ted Cruz (Tex.)says, “Climate change is not science, it’s religion.”Sen. Marco Rubio (Fla.) at the moment seems to acknowledge that climate change might be real but opposes any action to deal with it.

Well, you may say, Trump revels in his stupidities, and most of the presidential candidates are appealing to the rightmost wing of their primary electorate at the moment. What about the grownups in the party, such as Senate Majority Leader Mitch McConnell (Ky.)?

Glad you asked.

In an op-ed for The Post published as President Obama traveled to Paris for the opening of the climate talks, McConnell slammed Obama’s policy for harming the middle class without measurably affecting climate change.

Does that mean, I asked the majority leader’s press secretary, that he believes climate change is real, and are there policies he would favor to mitigate the risk?

The spokesman answered: “While the Leader has spoken often on energy and the President’s policies, I don’t believe he’ll have anything new today. And as to the President’s policies, the President says he’s for ‘all of the above.’ He got that line from us. But as to his climate proposal and the Paris proposals, I think he’s spoken clearly on that in his op-ed. I hope that helps.”

I tried once more: “So as to whether he believes climate change is real, or would favor any policies to mitigate it, I should just say, declined to answer?”

I didn’t hear back.

A genuine conservative, as Ronald Reagan’s secretary of state George P. Shultz has written, would acknowledge uncertainties in climate science but look for rational, market-based policies to lessen the risk without slowing economic growth. A revenue-neutral carbon tax, as in a bill Rep. Chris Van Hollen (D-Md.) has introduced, fits the description precisely.

What then explains the know-nothingism of today’s Republicans? Some of them see scientists as part of a left-wing cabal; many of them doubt government’s ability to do anything, let alone something as big as redirecting the economy’s energy use. Almost all of them, along with quite a few Democrats, would rather not tell voters that energy prices need to rise for the sake of the environment.

Their donors in the oil and gas industry encourage their prejudices. Three years ago, Grover Norquist, the Republicans’ anti-tax enforcer, said that a carbon tax wouldn’t violate his no-tax-increase pledge if the proceeds were returned by lowering the income tax, though he made clear he didn’t like the idea.

The next morning, the lobbying arm of the oil and gas industry swung into action. “Grover, just butch it up and oppose this lousy idea directly,”the American Energy Alliance said. “This word-smithing is giving us all headaches.”

For most of us, the reaction to this would have been: Butch it up? But Norquist got the message and within hours issued a clarification: Only a constitutional amendment banning the income tax could justify a carbon tax.

So the industry deserves its share of blame, and that includes ExxonMobil, which hardly trumpets its views on the advantages of a carbon tax. (Its most alarming slide, on the 5-degree temperature rise, can’t be found on its public site.)

But blaming it all on Big Oil lets the politicians off too easily. Yes, McConnell represents a coal state, and, yes, he wants to preserve his Senate majority. If those considerations are more important to him than saving the planet, let him say so to our children and grandchildren. Let’s not blame the oil companies for the pusillanimity of people who are supposed to lead.

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