Scott Olson/Getty Images(CANNON BALL, N.D.) — The day after the U.S. Army Corps of Engineers announced that it will not approve an easement needed to permit the Dakota Access Pipeline to cross under Lake Oahe in North Dakota, sparking a wave of celebration throughout the protest camp, efforts to protest the construction of the pipeline were expected to resume Monday.

The announcement Sunday afternoon marked a major victory for the Native American tribes and thousands of environmentalists and other activists who have demonstrated in solidarity with their cause. Many who gathered at the site of the protest met around a communal “sacred” fire to discuss the victory, and some were too overcome with emotion to put their thoughts into words.

But work on the controversial crude oil pipeline may not have been defeated by Sunday’s announcement, at least not permanently, and because of this, the protest camp is expected to resume activity Monday.

Many vowed to remain at camp until a definitive rejection of the pipeline could be secured.

Additionally, at least 2,000 military veterans who arrived Sunday to act as a “human shield” between the protesters and the police have started the process of taking over camp security, a circumstance that had led to mixed emotions around the camp due to the complicated, and often brutal history between U.S. armed forces and Native Americans.

The vets, led by Wesley Clark Jr., son of retired general and former presidential candidate Wesley Clark, are expected to be present at the camp until Dec. 7. Donations to a GoFundMe account launched by Clark in support of Veterans for Standing Rock, a group he claimed would “assemble as a peaceful, unarmed militia at the Standing Rock Indian Reservation,” passed the $1 million dollar mark Sunday morning.

Native American groups and environmental activists have been protesting since summer to block construction of the 1,172-mile pipeline that would have cut across four states and transport crude oil from North Dakota’s oil fields to refinery markets in Illinois.

The activists, who call themselves “water protectors,” say that the pipeline traverses culturally sacred sites and poses a risk to the Standing Rock Sioux Tribe’s water supply.

Prominent progressives, including Sen. Bernie Sanders, I-Vt., applauded the Army Corps’ decision to halt work on the pipeline, saying in a statement, “in the year 2016, we should not continue to trample on Native American sovereignty. We should not endanger the water supply of millions of people.”

Canadian author and environmental activist Naomi Klein wrote in The Nation that the Army Corps’ announcement demonstrated the efficacy of protest as a way for activists to make gains in the movement to combat man-made climate change.

“The line between resistance and results is bright and undeniable. That kind of victory is rare precisely because it’s contagious, because it shows people everywhere that organizing and resistance is not futile. And as Donald Trump moves closer and closer to the White House, that message is very important indeed,” Klein wrote.

President-elect Donald Trump said last week for the first time that he supports the completion the pipeline. Trump has been accused of being dismissive of the concerns of scientists and activists regarding the potential threat posed by man-made climate change.

In a meeting last month with The New York Times, Trump appeared to soften his tone on the subject by acknowledging “connectivity” between human activity and climate change.

“I think there is some connectivity. Some, something,” he said in the meeting.

House Speaker Paul Ryan voiced his disapproval last night of the Army Corps’ decision, tweeting that it was “big-government decision-making at its worst.”

“I look forward to putting this anti-energy presidency behind us,” Ryan wrote, anticipating the start of Trump’s administration next month.

Rep. Tulsi Gabbard, D-Hawaii, who gained prominence when she left the Democratic National Committee to campaign for Bernie Sanders during his bid for the Democratic presidential nomination this year, and was among the more high profile veterans attending the protests at Standing Rock, urged caution to activists, suggesting on Twitter that more fights were likely on the horizon.

“While we celebrate today’s news, we cannot be complacent. We must continue to protect our water and preserve our land,” she wrote on Sunday night.

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