Prior to his arrest in front of the White House, the Rev. Jim Antal said that the proposed Keystone XL pipeline is a "deal with the devil."

Dressed in a black clergy shirt in 90-degree heat, the 61-year-old president of the Massachusetts Conference of the United Church of Christ said climate change was at the front of his mind when he came with dozens of protesters Saturday to participate in a sit-in at President Obama's doorstep.

The pipeline -- which would transport a form of oil that releases more carbon emissions in the production process than does traditional oil -- is a symbol of the "moral issue of our time," said Antal. The protesters are urging the Obama administration to deny Keystone XL a permit.

It is his first arrest since the 1980s, when he protested against nuclear weapons. The climate issue is bringing him to civil disobedience again, he said, since it also is a rare challenge involving humans ushering in the destruction of the planet with their free will. Climate change now dominates his weekly sermons, he said.

"This is a watershed moment for President Obama," he said, wearing an Obama pin on his shirt. "He has the opportunity to be the person who future generations will look back at and say, 'Here's somebody who stopped being a politician and started being an advocate for humanity.'"

Antal was one of about 70 protesters arrested Saturday as the lobbying battle over the Keystone XL pipeline moves into a critical phase. If built, the pipeline would roughly double the amount of Canadian crude coming to the United States, bringing in 700,000 additional daily barrels. Within days, the State Department is expected to release a final environment impact statement on the $7 billion TransCanada project.

That will be followed by a final decision, expected this year, on whether the pipeline will get a thumbs-up from the U.S. government via a cross-border permit. If it does, construction could begin by 2012, according to TransCanada.

Supporters of Keystone XL say it is needed to wean the United States off Middle Eastern oil. In television ads and letter-writing campaigns, they have pushed back against assertions that the pipeline would worsen climate change and cause extensive environmental damage.

2-week campaign to pressure Obama

"The [United States] must make a decision -- import conflict-free crude from Canada or import it from repressive regimes like the Middle East or Libya," TransCanada spokesman Terry Cunha said Friday.

It is against this backdrop that more than a hundred activists from the United States and Canada came to Washington, D.C., for the first day of two weeks of rallies.

Led by 350.org founder Bill McKibben and former Carter administration official Gus Speth, they slept in church basements and underwent protest-training sessions before heading to Lafayette Park.

One by one, they marched to the White House black fence -- where they did not have a permit to sit -- lined up and chanted anti-Keystone XL slogans in unison next to a banner saying, "Climate change is not in our national interest."

After three warnings from U.S. Park Police to move, they were led away in handcuffs, with phone numbers written on their arms of people they could call to pick them up from jail.

It is a ritual that will reoccur until Sept. 3, with 50 to 100 people planning to face arrest daily. NASA scientist James Hansen, First Nations leaders and celebrities also are planning to appear.

Dozens of additional protesters stood across the street in the park, cheering and clapping as their colleagues were led away by police.

They included 33-year-old Heather Milton-Lightning, an activist working with First Nations in Canada. She said a range of issues prompted her to come to Washington, including worries from native Canadians that oil sands development is disrupting forests and wildlife patterns and creating toxic runoff from refineries into waterways.

"You might end up with a job doing tar sands development. But in the end of the day, you may have cancer and be dead," she said.

She said she did not participate in the sit-in out of concern that she would not be able to re-enter the United States in the future with an arrest record.

A common refrain in the crowd was the words of scientist Hansen, who wrote in a public missive this summer that full extraction of the oil sands in Canada would mean "game over" for the Earth when combined with burning of coal. With the world's second-largest oil reserves, Canada's oil sands region holds enough carbon to push the planet to a tipping point, according to Hansen.

The protesters also made a public call to Obama to remember his words from the campaign trail in 2008, when he said, "This was the moment when the rise of the oceans began to slow and our planet began to heal."

McKibben: 'We're not radicals'

For McKibben, who also was arrested Saturday, it is not a matter of whether the oil sands are worse than coal plants or other fossil fuels in terms of their emissions. With a federal climate bill dead, Keystone XL exemplifies the clearest-cut case for Obama to take a stand on global warming, he said.

"People want the guy from 2008 back," said McKibben about Obama. "The decision on the pipeline is now what the environmental movement is focused on."

He said he and other male protesters consciously wore suits and neckties to show "we're not radicals."

How much this resonates with the public is an open question. Polls show consistently that climate change ranks near the bottom of people's concerns when compared to other issues.

And if random pedestrians in Lafayette Park across from the White House are an indication, that sentiment prevails with some members of the public.

"I don't care about climate change, but I want my picture taken in front of the protesters," said one young woman standing in front of policemen on horseback. Another young person watching handcuffed individuals led to white police vans said, "What does that do? You're just wasting police resources."

But others said they had deep respect for the activists. A couple from Toronto said they were concerned about what oil sands production means for destruction of Canada's forests, as well as climate change.

Brian Joslin, a physical therapist visiting from Philadelphia, said that the action exemplified what democracy was all about. Climate change seems like a distant issue, and not one that is likely to resonate in the presidential campaign, he said as he watched the protesters.

"But there has been a lot of crazy weather lately," he said. "So I do worry about it."

Supporters of the pipeline have been engaging in their own lobbying campaigns via advertisements and public events.

They are quick to note that Canada currently releases about 2 percent of global greenhouse gases, with oil sands production constituting a fraction of that amount. The United States has a choice to boost national security while creating jobs surrounding the pipeline, they say (ClimateWire, July 25).

With gas prices high, many political analysts also say that the Obama administration is likely to approve the project despite any political concerns about offending a key segment of the president's voting base.

"While the administration is sensitive to criticisms from the environmental community, particularly those expressed through public protest, those likely will be overridden by concerns about the stagnant economy and energy prices and security," said Thomas Mann, an analyst at the Brookings Institution, a liberal-leaning think tank.