FILE - In a Dec. 5, 2012 file photo, foreman Javier Garcia works with his crew as they lower a section of pipe into the ground with cradles, along the TransCanada Keystone XL Pipeline section two near Winona, Texas. (Sarah A. Miller/AP)
Editorial writer and columnist

Building the Keystone XL pipeline, to speed the flow of crude from Canada’s oil sands to refineries in Texas, would be “game over for the climate,” says NASA-scientist-turned-climate-activist James E. Hansen. Heeding Hansen’s words, environmentalists have sworn to stop the project, which requires U.S. government approval.

Yet large, bipartisan majorities of the House and Senate support Keystone XL, as does 60 percent of the American public, according to the latest USA Today poll.

Today, it is still on hold, because Tuesday night 41 Senate Democrats voted against ending debate on a bill to green-light Keystone XL, thus thwarting what might have been a disastrous exercise of democracy.

In short, the filibuster may have just saved the planet, at least for now.

Or so it must be believed by Keystone XL’s opponents — even though they include some of the same people who decried the filibuster, not unreasonably, as an obstructionist, anti-majoritarian evil when Republicans employed it against President Obama’s health-care reform, cap-and-trade and other progressive legislation.

Here's a look at the proposed route and some of the facts and controversies surrounding the pipeline.

Majority rule is not the only progressive principle some progressives seem ready to sacrifice on the anti-Keystone altar.

Remember the corrupting influence of money on politics? Billionaire Tom Steyer has spent millions on TV ads backing environmentalist Democrats and trashing the pipeline itself, thus purchasing outsize influence in the White House and the Democratic Party.

“On issues as critical as climate change, we will take action and work within the system that we’ve got until we can change it,” Steyer pragmatically told Forbes magazine.

Most of the time, liberals tout the job-creating potential of critical infrastructure projects, based on the indirect “multiplier effect” that even short-term construction can have on economic growth.

For Keystone XL, though, different rules apply. We are instructed, by Daniel Weiss of the Center for American Progress, among others, that the $8 billion project will create “only” 3,900 “direct” one-year construction jobs and a mere 50 permanent ones. Forget the 42,000 jobs that a State Department analysis said would be “supported” by the project.

Construction unions understand that employment in their field is inherently temporary in the sense that it ends when the building is built. They strongly favor Keystone XL. Yet this reliably Democratic middle-class constituency is also being thrown under the anti-Keystone bus.

The least attractive violation of progressive values by Keystone XL opponents’ was their attempt to recast this joint project of Canada and the United States in xenophobic terms.

One Steyer-financed ad warned that China is “counting on the U.S. to approve TransCanada’s pipeline to ship oil through America’s heartland and out to foreign countries like theirs.” The only basis for this claim was that state-owned Chinese companies have a modest investment in Canada’s oil sands. The Post’s Fact Checker, Glenn Kessler, awarded the ad four Pinocchios, noting that “it relies on speculation, not facts, to make insinuations and assertions not justified by the reality.”

Speaking of the planet, perhaps the only person on it who still hasn’t made up his mind about Keystone XL is President Obama, though his dithering has recently given way to expressions depressingly reminiscent of those in the Steyer ad.

“Understand what this project is,” he said at a news conference in Burma last week. “It is providing the ability of Canada to pump their oil, send it through our land down to the Gulf [Coast], where it will be sold everywhere else.” Their oil. Our land.

Yet his own State Department’s exhaustive review of the project found that re-exports of the oil, either as crude or in refined form, were unlikely.

Hypocrisy and rhetorical flimflam are standard in politics, and liberals are not the only guilty parties in the Keystone XL battle. Keystone XL proponents have undoubtedly tapped corporate coffers to fund their share of exaggerations about the project’s benefits. And of course climate change is real and must be addressed.

But in this case progressives are not only being intellectually dishonest and traducing their values, they’re doing so pointlessly: This end doesn’t justify these means.

Far from being “game over” for the planet, Keystone XL would not boost greenhouse gas emissions significantly, according to State Department experts. With or without Keystone XL, Canada’s oil sands will still be turned into crude oil and shipped, often by rail, to markets in the United States and elsewhere. The environmental movement’s energies — not to mention Steyer’s millions — would be far better spent elsewhere.

In their tendentious effort to deny these realities, progressives risk violating yet another cherished principle that, in their view, distinguishes them from the right: that of letting facts and science, not ideology, determine policy.

Campaigning for a symbolic victory over the fossil-fuel industry, they may end up with a pyrrhic one — if any.

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