The Obama administration’s foot-dragging on approving the Keystone XL pipeline has cost the U.S. economy a whopping $175 billion over the last seven years, or $42 million a day, according to a new report by the right-leaning American Action Forum.

“The Keystone XL pipeline has the potential to bring huge gains to the United States, including energy independence, increased security and jobs,” wrote AAF’s energy policy director Kimberly VanWyhe in a new report.

In September 2008, the company TransCanada first sought approval from the Obama administration to build its 1,179-mile pipeline from Alberta to the Gulf Coast. Environmentalists, however, were quick to oppose the project on the grounds the oil it was carrying would exacerbate global warming.

Since President Barack Obama took office in 2009, the State Department has sat on the pipeline’s approval and not issued its recommendation on whether or not the project is in the national interest. That delay has added up, according to AFF, costing the U.S. economy $15 billion per year.

“At today’s price of crude at $51.76, this would gross over $42 million dollars a day or roughly $15 billion per year,” wrote VanWyhe, noting how much economic activity was lost by not moving 830,000 barrels of oil across the Canadian border.

Environmentalists have successfully pressured the Obama administration to delay approving the pipeline through mass protests, reports claiming oil sands causes more global warming than conventional oil and arguments the project would raise gas prices. Now eco-activists are attacking Democratic presidential candidate Hillary Clinton for not openly opposing the project.

Clinton recently came out with a plan to boost U.S. reliance on green energy and get half a billion solar panels installed. Green groups welcomed the pledge, but said Clinton has a long way to go to prove she’s “greener” than her primary opponents.

“Now, we need Clinton to show she understands the other half of the climate change equation — and prove she has the courage to stand up against fossil fuel projects like offshore and Arctic drilling, coal leasing in the Powder River basin, and the Keystone XL pipeline,” Bill McKibben, a prominent environmentalist who started the anti-fossil fuel group 350.org, said in a statement.

Clinton’s green energy plan release, however, was colored by questions over the Democrat’s support for Keystone XL — which was pending approval while she was secretary of state. Clinton has so far refused to answer any questions about the pipeline.

“This is President Obama’s decision, and I will not second-guess him,” Clinton said at a campaign stop. “If it’s undecided when I become president, I will answer your question.”

Earlier this year, Obama vetoed legislation that would have approved the pipeline that passed out of Congress. Republicans argued the pipeline would increase U.S. energy security and boost the economy.

Obama justified his veto by arguing Congress was trying to circumvent the regulatory process. The State Department has set no final date for it to rule on the pipeline. That could mean billions more in lost economic activity, according to AAF.

“Fiscally, economically, environmentally and strategically speaking this project is a win,” VinWyhe wrote. “After nearly 7 years and $175 billion in lost economic activity, it is time for the construction of Keystone to come to fruition in order to allow Americans to experience the economic benefits.”

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