Hillary Clinton and Bernie Sanders clashed many times last year, but they’re united in their opposition to President Trump’s latest executive order rolling back environmental protections.

By signing the Energy Independence executive order at the Environmental Protection Agency’s (EPA) headquarters Wednesday, Trump followed through on a campaign promise to start dismantling the Clean Power Plan — the centerpiece of former President Barack Obama’s climate legacy.

The former rivals for the Democratic presidential nomination were outraged that Trump effectively made climate skepticism U.S. national policy and forfeited the country’s role as a world leader in the fight against climate change.

“These are more than statistics, they’re American lives at risk because this administration willfully ignores the science,” Clinton tweeted overnight. She also shared sample scripts, prepared by environmentalist group NextGen Climate, for citizens to voice their displeasure with Trump’s climate policy to their respective governors.

Sanders, a U.S. senator representing Vermont, took to Twitter to denounce Trump’s order, and he vowed to challenge it at every step.

“Mr. Trump: You are threatening the lives of our children and grandchildren. We will fight you every step of the way,” he wrote.

The Clean Power Plan was central to the Obama administration’s strategy for complying with the groundbreaking Paris Agreement of December 2015, in which 194 nations vowed to reduce carbon emissions to limit the increase in average temperature worldwide to below 2 degrees Celsius.

Former Secretary of State Hillary Clinton and Sen. Bernie Sanders. (Photos: Justin Sullivan/Getty Images)

The largest concentrated source of carbon dioxide emissions in the U.S. is power plants. According to the EPA, by 2030 the Clean Power Plan would have cut carbon pollution from power plants by roughly 30 percent from 2005 levels. In addition, by reducing emissions of particulates and other pollutants, it would have prevented 140,000 to 150,000 childhood asthma attacks and averted 2,700 to 6,600 premature deaths.

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Sanders also recorded a short video in which he chastises Trump for claiming that Obama “decimated” the coal industry. He pointed out that coal-mining jobs have been declining for decades — since long before Obama took office, reflecting economic factors including falling prices for natural gas.

The senator, who has a 91 percent lifetime score from the League of Conservation Voters, called for a move toward clean and sustainable energy sources, such as wind, solar and geothermal, rather than a push back toward fossil fuels.

“President Trump’s anti-environmental executive orders are a disaster. They are a threat to the future of this country and to the future of the world,” Sanders said. “It is beyond belief that we have the leader of the most powerful country on earth not believing in science.”

Trump presented the controversial executive order as his latest action in a series intended to stimulate the economy and create jobs. Flanked by coal miners and industry executives, Trump criticized what he called “the war on coal,” complete with “job-killing regulations” and “government intrusion.” The speech conformed with Trump’s overall “America First” message.

“We will unlock job-producing natural gas, oil and shale energy,” Trump said. “We will produce American coal to power American industry. We will transport American energy through American pipelines, made with American steel.”

Shortly after the executive order was signed, the American Association for the Advancement of Science (AAAS) released a statement affirming that the scientific evidence regarding climate change is clear: Climate change primarily driven by human activities is already happening and affecting people and our environment.

Rush Holt, the chief executive officer of the AAAS, emphasized that scientific research helps guide informed responses to climate change by communities, businesses and governmental agencies.

“There is much our nation can do to address the risks that climate change poses to human health and safety, but disregarding scientific evidence puts our communities in danger,” Holt said. “We encourage the White House and Congress to support the evidence on climate change, and welcome opportunities to bring scientists to meet with policymakers to discuss the state of the science, the degree of scientific understanding on climate change, and other areas of concern and interest.”

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