On Tuesday Daryl Hannah was arrested near the White House while protesting possible approval of the Keystone XL oil pipeline.  The Keystone XL project is designed to carry large quantities of oil from Canadian oil sands to refineries on the U.S. Gulf Coast.  As such, the Keystone XL project is one of the most important steps America can take toward energy security.  That seems like good reason to approve the pipeline, but environmentalists like Ms. Hannah are determined to block it.

Ms. Hannah is certainly free to express her opinions as she likes, but it seems odd that anyone would oppose construction of a pipeline that would help secure America's energy future by ensuring supplies from a reliable ally like Canada.  It seems odd, but Hannah was not alone at the White House.  She was joined by some 2,000 protesters, 500 of whom have been arrested.  These include Elijah Zarlin, a former senior writer on Obama's 2008 campaign.  Another was Bill McKibben, organizer of 350.org, an online environmental group and resident scholar at Middlebury College.  McKibben is the author of a string of global warming and anti-growth books dating back to 1989.  He, too, expressed support for Obama in 2008 in hopes the presidential candidate would end America's reliance on fossil fuels.

In fact, nearly every environmentalist group in the country has lined up in opposition to the pipeline.  And this despite the fact that the Keystone XL has passed the most extensive environmental review ever conducted for a pipeline project.  The Sierra Club Compass calls the Keystone XL a "dirty tar sands oil monstrosity."  The club's president warns Obama of dire political repercussions should the pipeline be approved.  Friends of the Earth leader Erich Pica stated that if Obama approves the pipeline, it will be "open season on the president's record" on the environment.  An official with the Natural Resources Defense Council stressed that approval would be "a dirty legacy for president Obama."

It is not, of course, the pipeline itself that environmental radicals view as "dirty."  It is what it carries -- especially since what it carries comes from the Canadian oil sands.  The environmental lobby has worked overtime to create the impression that energy from the oil sands is "dirtier" than conventional oil, despite the fact that this heavy oil can be refined with no more than 2% additional carbon emissions.

The truth is, it is not the fact that oil sands are "dirty" that upsets greens.  It is that they are plentiful, thus ensuring a vast 50-year supply of cheap and affordable fossil fuel.  It is estimated that Canadian oil sands contain 1.75 trillion barrels of recoverable oil, an amount equal to current global reserves of conventional oil.  The left is determined to block further entry of oil sands production into the U.S. because that production would ensure continued reliance on fossil fuels for decades to come.

As to what might take the place of oil, natural gas, and coal, environmentalists insist that America's needs can be met by a combination of conservation and "sustainable" alternatives (wind and solar).  The fact that wind and solar now supply only 2% of the nation's needs does not seem to trouble them.  Maybe because they are thinking in terms of something like 98% conservation and 2% alternatives.  In other words, an end to practically all transport, commerce, construction, and new development -- as well as cessation of practically all current activities dependent on energy.  No planes, trains, or cars.  No heating or air conditioning.  No manufacturing or transport.  Only green vistas of land returned to wilderness, and lots of yoga.

Nothing will convince the green activist when it comes to the Keystone XL, even the fact that the project has, after exhaustive review and delay, at last received State Department environmental approval.  (For those who did not realize the State Department was in the game of environmental review, guess again.  With Obama in charge, every regulatory body, from the National Labor Relations Board to the Securities and Exchange Commission, not to mention the federal courts and the EPA, is in the business of environmental review.)

So as not to totally freak out the administration's green supporters, Secretary of State Clinton insisted that the Keystone XL was still a long way from State Department approval.  Obama himself announced that he had nothing to do with the decision.  (He is apparently not aware of the fact that he is Hillary's boss.)  But, sensing the administration might for once decide to place national interest ahead of global warming mythology, environmental radicals have begun beating the drums in the Capitol.  Thus, the arrest of Daryl Hannah.

None of the pipeline's opponents has addressed the fact that the Keystone XL would be in the national interest.  It would, after all, transport reliable supplies of Canadian oil, as much as 400,000 barrels a day, to refineries on the Gulf Coast.  Transportation via underground pipeline is more secure and more environmentally safe than transport via tanker.  And supplies from Canada are more secure, politically and otherwise, than those from the Middle East or Latin America.  The result would be a long-term, stable, and clean source of affordable energy.

An important bonus is the fact that the pipeline would create jobs.  According to TransCanada, the pipeline operator, the project would create an immediate 13,000 jobs in construction and other fields, with an additional 118,000 secondary jobs supporting the pipeline.  It would pump $20 billion into the economy.  And it would lower the long-term cost of fuel for American consumers.

Given the reality that the U.S. will be importing much of its oil for decades to come, isn't it better to get it from a stable ally like Canada than from Venezuela or the Middle East?

Apparently, Ms. Hannah, star of such megahits as Shark Swarm and Kung Ku Killer, doesn't think so.  One is tempted to say that Ms. Hannah should stick to acting, but given her recent film work, maybe that's not such a good idea either.

Jeffrey Folks is author of many books and articles on American culture and politics.