If there were any lingering doubts over Donald Trump’s enthusiasm for shoving the U.S. back into the smoggy embrace of fossil fuels, his decision to revive the Keystone XL and Dakota Access pipelines banishes them utterly.

Trump has thrown down the most provocative gauntlet possible to the environmental movement, which now sees its worst fears crystalizing within a few days of the inauguration. Those Trump Tower chats with Al Gore about climate change—and Ivanka Trump’s apparent concern over the issue—now vanish over the horizon. This will be an aggressively pro-oil and gas administration, even if that means boiling the planet.

“Donald Trump has been in office for four days and he’s already proving to be the dangerous threat to our climate we feared he would be,” said Michael Brune, executive director of the environmental organization the Sierra Club.

“Simply put, Donald Trump is who we thought he is: a person who will sell off Americans’ property and tribal rights, clean air and safe water to corporate polluters.”

The resurrection of the Keystone XL pipeline will cause particular anguish among climate activists. Protests over the plan to run the 1,200-mile pipeline from the Canadian tar sands to Texas dogged Barack Obama throughout his presidency. Finally, in 2015, Obama announced that the pipeline would not go ahead, stating that the refusal showed the US is “now a global leader when it comes to taking serious action to fight climate change”.

That climate leadership is now in danger of being eroded, at a time when the world’s major polluters must drastically reduce greenhouse gas emissions if the world is to avoid dangerous global warming. The tribes and other groups that fought for years against Keystone will now to have to wearily re-enter the fray against TransCanada, the company behind the project. Following Obama’s refusal, TransCanada sued the US for $15 billion under the North American Free Trade Agreement.

The Dakota Access pipeline is a similarly massive pipeline project that would run from North Dakota to Illinois. The proximity of the pipeline to the Standing Rock Sioux reservation in North Dakota, and its crossing of the Missouri river, the tribe’s primary source of water, prompted a protest camp that unified Native American tribes in fierce opposition, often met with brutal force from the police.

Trump has invested in Energy Transfer Partners, the company behind Dakota Access, but his spokesman has claimed, without providing evidence, that the president has now removed this conflict of interest.

During the 2016 election campaign Trump promised to revive large energy projects and promised a “a big piece of the profits” for the American people. Republicans staunchly opposed Obama’s restrictions on oil and gas development, claiming they held back the U.S. economy. Now, more extraction looks likely to get the green light, such as drilling the Arctic Ocean, which Obama banned in his final days in office.

With the former chief executive of ExxonMobil, Rex Tillerson, set to become secretary of state, and a cabinet packed with those who deny the science of climate change, it perhaps isn’t surprising that Trump has decided to push forward these projects so early. But Democrats and green groups opposing this agenda now face fights on a daunting range of fronts, and it’s not certain that protests over Native American rights and the future livability of the planet will resonate at all in the White House.

Activists are still trying their best to sound defiant. “It’s a dark day for reason, but we will continue the fight,” said Bill McKibben, co-founder of climate activist group 350.org.

“This is not a done deal. The last time around, TransCanada was so confident they literally mowed the strip where they planned to build the pipeline, before people power stopped them. People will mobilize again.”