WASHINGTON — The campaign ad appeared during the presidential contest of 2008. Rapid-fire images of belching smokestacks and melting ice sheets were followed by a soothing narrator who praised a candidate who had stood up to President George W. Bush and “sounded the alarm on global warming.”
It was not made for a Democrat, but for Senator John McCain, who had just secured the Republican nomination.
It is difficult to reconcile the Republican Party of 2008 with the party of 2017, whose leader, President Trump, has called global warming a hoax, reversed environmental policies that Mr. McCain advocated on his run for the White House, and this past week announced that he would take the nation out of the Paris climate accord, which was to bind the globe in an effort to halt the planet’s warming.
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The Republican Party’s fast journey from debating how to combat human-caused climate change to arguing that it does not exist is a story of big political money, Democratic hubris in the Obama years and a partisan chasm that grew over nine years like a crack in the Antarctic shelf, favoring extreme positions and uncompromising rhetoric over cooperation and conciliation.
“Most Republicans still do not regard climate change as a hoax,” said Whit Ayres, a Republican strategist who worked for Senator Marco Rubio’s presidential campaign. “But the entire climate change debate has now been caught up in the broader polarization of American politics.”
“In some ways,” he added, “it’s become yet another of the long list of litmus test issues that determine whether or not you’re a good Republican.”
Since Mr. McCain ran for president on climate credentials that were stronger than his opponent Barack Obama’s, the scientific evidence linking greenhouse gases from fossil fuels to the dangerous warming of the planet has grown stronger. Scientists have for the first time drawn concrete links between the planet’s warming atmosphere and changes that affect Americans’ daily lives and pocketbooks, from tidal flooding in Miami to prolonged water shortages in the Southwest to decreasing snow cover at ski resorts.
That scientific consensus was enough to pull virtually all of the major nations along. Conservative-leaning governments in Britain, France, Germany and Japan all signed on to successive climate change agreements.
Yet when Mr. Trump pulled the United States from the Paris accord, the Senate majority leader, the speaker of the House and every member of the elected Republican leadership were united in their praise.
Those divisions did not happen by themselves. Republican lawmakers were moved along by a campaign carefully crafted by fossil fuel industry players, most notably Charles D. and David H. Koch, the Kansas-based billionaires who run a chain of refineries (which can process 600,000 barrels of crude oil per day) as well as a subsidiary that owns or operates 4,000 miles of pipelines that move crude oil.
Government rules intended to slow climate change are “making people’s lives worse rather than better,” Charles Koch explained in a rare interview last year with Fortune, arguing that despite the costs, these efforts would make “very little difference in the future on what the temperature or the weather will be.”
Republican leadership has also been dominated by lawmakers whose constituents were genuinely threatened by policies that would raise the cost of burning fossil fuels, especially coal. Senator Mitch McConnell of Kentucky, always sensitive to the coal fields in his state, rose through the ranks to become majority leader. Senator John Barrasso of Wyoming also climbed into leadership, then the chairmanship of the Committee on Environment and Public Works, as a champion of his coal state.
Mr. Trump has staffed his White House and cabinet with officials who have denied, or at least questioned, the existence of global warming. And he has adopted the Koch language, almost to the word. On Thursday, as Mr. Trump announced the United States’ withdrawal, he at once claimed that the Paris accord would cost the nation millions of jobs and that it would do next to nothing for the climate.
Beyond the White House, Representative Lamar Smith of Texas, chairman of the House Science Committee, held a hearing this spring aimed at debunking climate science, calling the global scientific consensus “exaggerations, personal agendas and questionable predictions.”
A small core of Republican lawmakers — most of whom are from swing districts and are at risk of losing their seats next year — are taking modest steps like introducing a nonbinding resolution in the House in March urging Congress to accept the risks presented by climate change.
But in Republican political circles, speaking out on the issue, let alone pushing climate policy, is politically dangerous. So for the most part, these moderate Republicans are biding their time, until it once again becomes safe for Republicans to talk more forcefully about climate change. The question is how long that will take.
“With 40 percent of Florida’s population at risk from sea-level rise, my state is on the front lines of climate change,” said Representative Carlos Curbelo, Republican of Florida. “South Florida residents are already beginning to feel the effects of climate change in their daily lives.”
‘The Turning Point’
It was called the “No Climate Tax” pledge, drafted by a new group called Americans for Prosperity that was funded by the Koch brothers. Its single sentence read: “I will oppose any legislation relating to climate change that includes a net increase in government revenue.” Representative Jim Jordan, Republican of Ohio, was the first member of Congress to sign it in July 2008.
The effort picked up steam the next year after the House of Representatives passed what is known as cap-and-trade legislation, a concept invented by conservative Reagan-era economists.
The idea was to create a statutory limit, or cap, on the overall amount of a certain type of pollution that could be emitted. Businesses could then buy and sell permits to pollute, choosing whether to invest more in pollution permits, or in cleaner technology that would then save them money and allow them to sell their allotted permits. The administration of the first President George Bush successfully deployed the first national cap-and-trade system in 1990 to lower emissions of the pollutants that cause acid rain. Mr. McCain pushed a cap-and-trade proposal to fight climate change.
“I thought we could get it done,” recalled Henry A. Waxman, a retired House Democrat who led the cap-and-trade push in 2009. “We just had two candidates from the Republican and Democratic parties who had run for president and agreed that climate change was a real threat.”
Conservative activists saw the legislative effort as an opportunity to transform the climate debate.
With the help of a small army of oil-industry-funded academics like Wei-Hock Soon of Harvard Smithsonian and think tanks like the Competitive Enterprise Institute, they had been working to discredit academics and government climate change scientists. The lawyer and conservative activist Chris Horner, whose legal clients have included the coal industry, gathered documents through the Freedom of Information Act to try to embarrass and further undermine the climate change research.
Myron Ebell, a senior fellow with the Competitive Enterprise Institute, worked behind the scenes to make sure Republican offices in Congress knew about Mr. Horner’s work — although at the time, many viewed Mr. Ebell skeptically, as an extremist pushing out-of-touch views.
In 2009, hackers broke into a climate research program at the University of East Anglia in England, then released the emails that conservatives said raised doubts about the validity of the research. In one email, a scientist talked of using a statistical “trick” in a chart illustrating a recent sharp warming trend. The research was ultimately validated, but damage was done.
As Congress moved toward actually passing climate change legislation, a fringe issue had become a part of the political mainstream.
“That was the turning point,” Mr. Horner said.
Unshackled by the Supreme Court’s Citizens United decision and other related rulings, which ended corporate campaign finance restrictions, Koch Industries and Americans for Prosperity started an all-fronts campaign with television advertising, social media and cross-country events aimed at electing lawmakers who would ensure that the fossil fuel industry would not have to worry about new pollution regulations.
Their first target: unseating Democratic lawmakers such as Representatives Rick Boucher and Tom Perriello of Virginia, who had voted for the House cap-and-trade bill, and replacing them with Republicans who were seen as more in step with struggling Appalachia, and who pledged never to push climate change measures.
But Americans for Prosperity also wanted to send a message to Republicans.
Until 2010, some Republicans ran ads in House and Senate races showing their support for green energy.
“After that, it disappeared from Republican ads,” said Tim Phillips, the president of Americans for Prosperity. “Part of that was the polling, and part of it was the visceral example of what happened to their colleagues who had done that.”
What happened was clear. Republicans who asserted support for climate change legislation or the seriousness of the climate threat saw their money dry up or, worse, a primary challenger arise.
“It told Republicans that we were serious,” Mr. Phillips said, “that we would spend some serious money against them.”
By the time Election Day 2010 arrived, 165 congressional members and candidates had signed Americans for Prosperity’s “No Climate Tax” pledge.
Most were victorious.
“The midterm election was a clear rejection of policies like the cap-and-trade energy taxes that threaten our still-fragile economy,” said James Valvo, then Americans for Prosperity’s government affairs director, in a statement issued the day after the November 2010 election. Eighty-three of the 92 new members of Congress had signed the pledge.
Even for congressional veterans, that message was not missed. Representative Fred Upton, a Michigan Republican who once called climate change “a serious problem” and co-sponsored a bill to promote energy-efficient light bulbs, tacked right after the 2010 elections as he battled to be chairman of the powerful House Energy and Commerce Committee against Joe Barton, a Texan who mocked human-caused climate change.
Mr. Upton deleted references to climate change from his website. “If you look, the last year was the warmest year on record, the warmest decade on record. I accept that,” he offered that fall. “I do not say that it’s man-made.”
Mr. Upton, who has received more than $2 million in campaign donations from oil and gas companies and electric utilities over the course of his career, won the chairmanship and has coasted comfortably to re-election since.
Two years later, conservative “super PACs” took aim at Senator Richard G. Lugar of Indiana, a senior Republican who publicly voiced climate concerns, backed the creation of a Midwestern cap-and-trade program and drove a Prius. After six Senate terms, Mr. Lugar lost his primary to a Tea Party challenger, Richard E. Mourdock. Although Mr. Lugar says other reasons contributed, he and his opponents say his public views on climate change played a crucial role.
“In my own campaign, there were people who felt strongly enough about my views on climate change to use it to help defeat me, and other Republicans are very sensitive to that possibility,” Mr. Lugar said in an interview. “So even if they privately believe we ought to do something about it, they’re reticent, especially with the Republican president taking the views he is now taking.”
Obama Feeds the Movement
After winning re-election in 2012, Mr. Obama understood his second-term agenda would have to rely on executive authority, not legislation that would go nowhere in the Republican-majority Congress. And climate change was the great unfinished business of his first term.
To finish it, he would deploy a rarely used provision in the Clean Air Act of 1970, which gave the Environmental Protection Agency the authority to issue regulations on carbon dioxide.
“If Congress won’t act soon to protect future generations, I will,” he declared in his 2013 State of the Union address.
The result was the Clean Power Plan, which would significantly cut planet-warming emissions by forcing the closing of hundreds of heavy-polluting coal-fired power plants.
The end run around Congress had consequences of its own. To Republican (and some Democratic) critics, the Clean Power Plan exemplified everything they opposed about Mr. Obama: He seemed to them imperious, heavy-handed, pleasing to the elites on the East and West Coasts and in the capitals of Europe, but callous to the blue-collar workers of coal and oil country.
“It fed into this notion of executive overreach,” said Heather Zichal, who advised Mr. Obama on climate policy. “I don’t think there was a good enough job on managing the narrative.”
Republicans who had supported the climate change agenda began to defect and have since stayed away.
“On the issue of climate change, I think it’s happening,” Mr. McCain said in a CNN podcast interview last April. But, he said, “The president decided, at least in the last couple years if not more, to rule by edict.”
Mr. Obama’s political opponents saw the climate rules as a ripe opportunity. “When the president went the regulatory route, it gave our side more confidence,” Mr. Phillips said. “It hardened and broadened Republican opposition to this agenda.”
Starting in early 2014, the opponents of the rule — including powerful lawyers and lobbyists representing many of America’s largest manufacturing and industrial interests — regularly gathered in a large conference room at the national headquarters of the U.S. Chamber of Commerce, overlooking the White House. They drafted a long-game legal strategy to undermine Mr. Obama’s climate regulations in a coordinated campaign that brought together 28 state attorneys general and major corporations to form an argument that they expected to eventually take to the Supreme Court.
They presented it not as an environmental fight but an economic one, against a government that was trying to vastly and illegally expand its authority.
“This is the most significant wholesale regulation of energy that the United States has ever seen, by any agency,” Roger R. Martella Jr., a former E.P.A. lawyer who then represented energy companies, said at a gathering of industry advocates, making an assertion that has not been tested.
Attorneys General Step In
Republican attorneys general gathered at the Greenbrier resort in West Virginia in August 2015 for their annual summer retreat, with some special guests: four executives from Murray Energy, one of the nation’s largest coal mining companies.
Murray was struggling to avoid bankruptcy — a fate that had befallen several other coal mining companies already, given the slump in demand for their product and the rise of natural gas, solar and wind energy.
The coal industry came to discuss a new part of the campaign to reverse the country’s course on climate change. Litigation was going to be needed, the industry executives and the Republican attorneys general agreed, to block the Obama administration’s climate agenda — at least until a new president could be elected.
West Virginia’s attorney general, Patrick Morrisey, led the session, “The Dangerous Consequences of the Clean Power Plan & Other E.P.A. Rules,” which included, according to the agenda, Scott Pruitt, then the attorney general of Oklahoma; Ken Paxton, Texas’ attorney general; and Geoffrey Barnes, a corporate lawyer for Murray, which had donated $250,000 to the Republican attorneys general political group.
That same day, Mr. Morrissey would step outside the hotel to announce that he and other attorneys general would sue in federal court to try to stop the Clean Power Plan, which he called “the most far-reaching energy regulation in this nation’s history, drawn up by radical bureaucrats.”
Mr. Pruitt quickly became a national point person for industry-backed groups and a magnet for millions of dollars of campaign contributions, as the fossil fuel lobby looked for a fresh face with conservative credentials and ties to the evangelical community.
“Pruitt was instrumental — he and A.G. Morrisey,” said Thomas Pyle, a former lobbyist for Koch Industries, an adviser to Mr. Trump’s transition team and the president of a pro-fossil fuel Washington research organization, the Institute for Energy Research. “They led the charge and made it easier for other states to get involved. Some states were keeping their powder dry, but Pruitt was very out front and aggressive.”
After the litigation was filed — by Mr. Morrissey and Mr. Pruitt, along with other attorneys general who attended the Greenbrier meeting — Murray Energy sued in the federal court case as well, just as had been planned.
In February 2016, the Supreme Court indicated that it would side with opponents of the rule, moving by a 5-4 vote to grant a request by the attorneys general and corporate players to block the implementation of the Clean Power Plan while the case worked its way through the federal courts.
Trump Stokes the Fires
When Donald J. Trump decided to run for president, he did not appear to have a clear understanding of the nation’s climate change policies. Nor, at the start of his campaign, did he appear to have any specific plan to prioritize a huge legal push to roll those policies back.
Mr. Trump had, in 2012, said on Twitter, “The concept of global warming was created by and for the Chinese in order to make U.S. manufacturing non-competitive.” But he had also, in 2009, joined dozens of other business leaders to sign a full-page ad in the The New York Times urging Mr. Obama to push a global climate change pact being negotiated in Copenhagen, and to “strengthen and pass United States legislation” to tackle climate change.
However, it did not go unnoticed that coal country was giving his presidential campaign a wildly enthusiastic embrace, as miners came out in full force for Mr. Trump, stoking his populist message.
And the surest way for Mr. Trump to win cheers from coal crowds was to aim at an easy target: Mr. Obama’s climate rules. Hillary Clinton did not help her cause when she said last spring that her climate policies would “put a lot of coal miners and coal companies out of business.”
In May 2016, Mr. Trump addressed one of the largest rallies of his campaign: an estimated crowd of over 10,000 in Charleston, W.Va., where the front rows were crammed with mine workers.
“I’m thinking about miners all over the country,” he said, eliciting cheers. “We’re going to put miners back to work.”
“They didn’t used to have all these rules and regulations that make it impossible to compete,” he added. “We’re going to take it all off the table.”
Then an official from the West Virginia Coal Association handed the candidate a miner’s hat.
As he put it on, giving the miners a double thumbs-up, “The place just went nuts, and he loved it,” recalled Barry Bennett, a former adviser to Mr. Trump’s presidential campaign. “And the miners started showing up at everything. They were a beaten lot, and they saw him as a savior. So he started using the ‘save coal’ portions of the speech again and again.”
Mr. Trump’s advisers embraced the miners as emblematic of the candidate’s broader populist appeal.
“The coal miners were the perfect case for what he was talking about,” Mr. Bennett said, “the idea that for the government in Washington, it’s all right for these people to suffer for the greater good — that federal power is more important than your little lives.”
Mr. Trump took on as an informal campaign adviser Robert E. Murray — chief executive of the same coal company that had been working closely for years with the Republican attorneys general to unwind the Obama environmental legacy.
Mr. Murray, a brash and folksy populist who started working in coal mines as a teenager, is an unabashed skeptic of climate science. The coal magnate and Mr. Trump had a natural chemistry, and where Mr. Trump lacked the legal and policy background to unwind climate policy, Mr. Murray was happy to step in.
“I thank my lord, Jesus Christ, for the election of Donald Trump,” Mr. Murray said soon after his new friend won the White House.
Mr. Trump appointed Mr. Ebell, the Competitive Enterprise Institute fellow who had worked for years to undermine the legitimacy of established climate science, to head the transition team at E.P.A. Mr. Ebell immediately began pushing for an agenda of gutting the Obama climate regulations and withdrawing from the Paris Agreement.
When it came time to translate Mr. Trump’s campaign promises to coal country into policy, Mr. Murray and others helped choose the perfect candidate: Mr. Pruitt, the Oklahoma attorney general.
Mr. Trump, who had never met Mr. Pruitt before his election, offered him the job of E.P.A. administrator — putting him in a position to dismantle the environmental rules that he had long sought to fight in court.
Meanwhile, Mr. Trump wanted to be seen delivering on the promises he had made to the miners. As controversies piled up in his young administration, he sought comfort in the approval of his base.
In March, Mr. Trump signed an executive order directing Mr. Pruitt to begin unwinding the Clean Power Plan — and he did so at a large public ceremony at the E.P.A., flanked by coal miners and coal executives. Mr. Murray beamed in the audience.
Meanwhile, a battle raged at the White House over whether to withdraw the United States from the Paris agreement. Mr. Trump’s daughter Ivanka and his secretary of state, Rex W. Tillerson, urged him to remain in, cautioning that withdrawing could be devastating to the United States’ foreign policy credentials.
Murray Energy — despite its enormous clout with Mr. Trump and his top environmental official — boasts a payroll with only 6,000 employees. The coal industry nationwide is responsible for about 160,000 jobs, with just 65,000 directly in mining, according to the federal Energy Information Administration.
By comparison, General Electric alone has 104,000 employees in the United States, and Apple has 80,000. Their chief executives openly pressed Mr. Trump to stick with Paris, as did dozens of other major corporations that have continued to support regulatory efforts to combat climate change.
But these voices did not have clout in Washington, either in Congress or at the White House, when it comes to energy policy.
Mr. Trump’s senior adviser, Stephen K. Bannon, backed by Mr. Pruitt, told the president that pulling out of the deal would mean a promise kept to his base.
“It is time to put Youngstown, Ohio; Detroit, Michigan; and Pittsburgh, Pennsylvania — along with many, many other locations within our great country — before Paris, France,” Mr. Trump said in his Rose Garden speech on Thursday. “It is time to make America great again.”
The Science Gets Stronger
The recognition that human activity is influencing the climate developed slowly, but a scientific consensus can be traced to a conference in southern Austria in October 1985. Among the 100 or so attendees who gathered in the city of Villach, nestled in the mountains along the Drava River, was Bert Bolin, a Swedish meteorologist and a pioneer in using computers to model the climate.
Dr. Bolin helped steer the conference to its conclusion: “It is now believed that in the first half of the next century a rise of global mean temperature could occur which is greater than any in man’s history,” he wrote in the conference’s 500-page report.
While the politics of climate change in the United States has grown more divided since then, the scientific community has united: Global warming is having an impact, scientists say, with sea levels rising along with the extremity of weather events. Most of the debate is about the extent of those impacts — how high the seas may rise, or how intense and frequent heavy storms or heat waves may be.
In recent years, many climate scientists have also dropped their reluctance to pin significant weather events on climate change. Studies have shown that certain events — a 2015 Australian heat wave, floods in France last year and recent high temperatures in the Arctic — were made more likely because of global warming.
But in Congress, reluctance to embrace that science has had no political downsides, at least among Republicans.
“We don’t yet have an example of where someone has paid a political price being on that side of it,” said Michael Steel, who served as press secretary for the former House speaker John A. Boehner, the Republican presidential candidate Jeb Bush and the current House speaker, Paul D. Ryan, during his 2012 run as Mitt Romney’s vice-presidential choice.
Instead, the messages of Mr. Pruitt still dominate.
“This is an historic restoration of American economic independence — one that will benefit the working class, the working poor and working people of all stripes,” Mr. Pruitt said on Thursday, stepping to the Rose Garden lectern after Mr. Trump. “We owe no apologies to other nations for our environmental stewardship.”
American voters — even many Republicans — recognize that climate change is starting to affect their lives. About 70 percent think global warming is happening, and about 53 percent think it is caused by human activities, according to a recent study by the Yale Program on Climate Change Communication. About 69 percent support limiting carbon dioxide emissions from coal-fired power plants.
But most public opinion polls find that voters rank the environment last or nearly last among the issues that they vote on. And views are divided based on party affiliation. In 2001, 46 percent of Democrats said they worried “a great deal” about climate change, compared with 29 percent of Republicans, according to a Gallup tracking poll on the issue. This year, concern among Democrats has reached 66 percent. Among Republicans, it has fallen, to 18 percent.
Until people vote on the issue, Republicans will find it politically safer to question climate science and policy than to alienate moneyed groups like Americans for Prosperity.
There will be exceptions. The 2014 National Climate Assessment, a report produced by 14 federal agencies, concluded that climate change is responsible for much of the flooding now plaguing many of the Miami area’s coastal residents, soaking homes and disrupting businesses, and Representative Curbelo is talking about it.
“This is a local issue for me,” Mr. Curbelo said. “Even conservatives in my district see the impact. It’s flooding, and it’s happening now.”
Mr. Curbelo helped create the House Climate Solutions Caucus, 20 Republicans and 20 Democrats who say they are committed to tackling climate change.
Mr. Curbelo is confident that as the impact of climate change spreads, so will the willingness of his Republican colleagues to join him.
Outside of Congress, a small number of establishment conservatives, including a handful of leaders from the Reagan administration, have begun pushing Washington to act on climate change. Earlier this year, James A. Baker III, one of the Republican Party’s more eminent senior figures, met with senior White House officials to urge them to consider incorporating a carbon tax as part of a broader tax overhaul package — a way to both pay for proposed cuts to corporate tax rates and help save the planet. A Reagan White House senior economist, Art Laffer; a former secretary of state, George P. Shultz; and Henry M. Paulson Jr., George W. Bush’s final Treasury secretary, have also pushed the idea.
“There are members from deep-red districts who have approached me about figuring out how to become part of this effort,” Mr. Curbelo said. “I know we have the truth on our side. So I’m confident that we’ll win — eventually.”
An earlier version of this article misstated when the Supreme Court stayed the Obama administration’s Clean Power Plan, which regulated emissions from coal-fired power plants. It was in February 2016, not April.