John McCain. Credit: Mark Wilson/Getty Images

Among the many battles Sen. John McCain waged in his storied career, it is easy to overlook his fight for U.S. action on climate change.

He wrote legislation that failed. He built a bipartisan coalition that crumbled. And when Congress came closest to passing a bill that embraced his central idea—a market-based cap-and-trade system—McCain turned his back.

And yet, McCain’s nearly decade-long drive on global warming had an impact that reverberates in today’s efforts to revive the U.S. role in the climate fight. In the Senate chamber and on the campaign trail, the Arizona Republican did more than any other U.S. politician has done before or since to advance the conservative argument for climate action.

Today’s efforts to recruit GOP members into the climate movement—appeals to conservative and religious values, the framing of climate change as a national security threat, efforts to stress market-based solutions and the role business leaders can play—all owe a debt to McCain.


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At the same time, McCain’s climate journey and its abrupt end serve as a cautionary tale of how far the Republican party has moved from a mainstream conservatism that is receptive to such appeals.

“What McCain did on climate is a really great reminder of where we need to get back to,” said Kevin Curtis, executive director of NRDC Action. As an environmental lobbyist on Capitol Hill in the 2000s, Curtis watched close-up as McCain crafted the first economy-wide climate legislation in the U.S. with one of his closest friends in the chamber, Sen. Joseph Lieberman of Connecticut, the Democrat who would later turn Independent.

“Lieberman and McCain were really good examples of a Democrat and Republican intentionally, consciously and thoughtfully trying to work across the aisle to build a 60-vote coalition in the Senate on climate,” said Curtis. “The point of looking at McCain’s legacy, I think, is not to just look back to the ‘good old days,’ but to look at what we need to get back to.”

John McCain and Joe Lieberman. Credit: Mark Wilson/Getty Images
Sens. John McCain, a Republican, and Joe Lieberman, a Democrat who would later become an Independent, fought their own parties’ leadership to bring cap-and-trade legislation to a vote in Congress. McCain died on Aug. 25, 2018, at the age of 81. Credit: Mark Wilson/Getty Images

Fred Krupp, president of Environmental Defense Fund and one of the political fathers of cap-and-trade, said McCain’s work on climate change was ahead of its time and laid the groundwork for the battle that continues.

“The McCain-Lieberman bill was the most substantial bipartisan effort our country has ever made to address the threat of climate change,” Krupp said. “The Senator will be remembered as being on the right side of this issue. He fought courageously in Congress to get them to take action on this problem long before we even understood how serious and urgent it is.”

“It was tough politics for him,” said former Sen. Tim Wirth of Colorado, who worked on international climate negotiations as undersecretary of state in the Clinton administration and for 15 years as president of the UN Foundation. “It was not easy in Arizona, and it was not easy as the conservative wing of the party was getting more vocal. But he kept hammering away at it, which from the perspective of today seems even more impressive.”

McCain’s Hearings Sought to Educate Congress on Climate Science

McCain began to focus intently on climate change soon after ending his roller-coaster 2000 presidential run. At seemingly every stop his Straight Talk Express campaign bus had made during the New Hampshire primary race (which he won by 19 points), he noticed he was peppered with questions from young people about climate change. Student activists from Dartmouth and other colleges actually had been recruited by two environmental groups that were working together—Ozone Action and U.S. Public Interest Research Group—to raise the profile of climate change as a political issue. They showed up at the rallies of every presidential candidate across the Granite State—sometimes holding signs or wearing flashy costumes—to press them with one question: “What is your plan?” Today, the organizers of the little 2000 New Hampshire climate campaign remember that every candidate—even then-Vice President Al Gore—ignored them, with one exception: McCain.

McCain had co-sponsored the 1990 bill that established a federal Global Change Research Program—legislation that passed the Senate unanimously—but the students’ question gnawed at him. “I do not have a plan,” McCain acknowledged in May 2000, at the first of three hearings on climate change he would convene that year as chair of the Senate Commerce, Science and Transportation Committee. “I am sorry to say that I do not have a plan because I do not have, nor do the American people have, sufficient information and knowledge.

“But I do believe that Americans, and we who are policymakers in all branches of government, should be concerned about mounting evidence that indicates that something is happening,” McCain said.

John McCain. Credit: Saul Loeb/Getty Images
“I do believe that Americans, and we who are policymakers in all branches of government, should be concerned about mounting evidence that indicates that something is happening.” —McCain, discussing climate change. Credit: Saul Loeb/Getty Images

The hearings were extraordinary, participants and observers say, in both their timing and their purpose. “He took this on at a time when climate change wasn’t mainstream or it wasn’t a topic people were talking about,” said Floyd DesChamps, now a technical management consultant, who was McCain’s lead staffer on the issue. The Senate, just three years earlier, had voted 95-0 against U.S. participation in the Kyoto Protocol, in a non-binding resolution to show bipartisan protest against a deal that included no obligations for fast-developing nations like China.

McCain didn’t have a prepackaged policy idea to showcase. “His instruction to us was we need a position on climate change—let’s develop one,” said DesChamps. The former staffer recalled that some witnesses “didn’t know what to expect” at first at a hearing chaired by a Republican, since opposition to climate action already was becoming GOP orthodoxy. But McCain invited some of the world’s top scientists to testify, including Robert Watson, then chairman of the Intergovernmental Panel on Climate Change. He probed them about ice breaking off of the Antarctic shelf, about the death of the coral reefs, about the effects of clouds. McCain said he was proceeding “on the premise that there is no such thing as a dumb question.”

“It was an excellent hearing and I gained a lot of respect for John McCain at that time,” said Kevin Trenberth, a senior scientist at the National Center for Atmospheric Research, who was one of the witnesses. “He appeared to have an open mind on what the answers were and what to do about it. My interpretation is that he realized that scientists recognized that climate change was a major looming issue: the science was convincing but there were good questions about what to do about the mounting evidence. … I had a genuine sense that he wanted to know the best information.”

“We sort of forget these days what hearings can really do for an issue,” said Washington, D.C.-based climate policy consultant Manik “Nikki” Roy, a former Capitol Hill staffer. “Hearings give the members and staff and the whole community an opportunity to dig into the facts, and that’s what [McCain] did. And he came away feeling we had a problem we needed to solve, which to me is a real conservative approach.”

After McCain’s GOP primary rival George W. Bush won the presidency in the contested 2000 election, and with the Senate divided 50-50, McCain set out to develop climate legislation that could win support across party lines. He reached across the aisle to his friend Lieberman, who happened to have been Gore’s running mate.

John McCain and Joe Lieberman. Credit: Mark Wilson/Getty Images
Lieberman believed McCain’s interest in climate change grew out of his genuine and long-standing concern about the environment. Credit: Mark Wilson/Getty Images

The partnership with Lieberman would feed into the speculation that McCain’s climate move was a challenge to Bush (see also this), who early in his presidency withdrew from the Kyoto accord and backed away from his own promise to address carbon pollution. Bush’s campaign had destroyed McCain’s momentum in the 2000 presidential race by spreading a barrage of negative and false rumors about McCain via push polls in the South Carolina primary.

But Lieberman believed McCain’s interest in climate change grew out of his genuine and long-standing concern about the environment. An avid outdoorsman who enjoyed hiking the Grand Canyon and who had worked to expand Western wilderness protections, McCain was a conservative conservationist in the tradition of Theodore Roosevelt, in Lieberman’s view. Also, Lieberman believed that McCain sought to emulate a fellow Arizonan who had been one of his mentors, former Rep. Morris Udall, a Democrat known for his humor and bipartisan consensus-seeking. Udall had been a champion of environmental causes before leaving Congress due to Parkinson’s disease in 1991. (Udall died in 1998.)

Colleagues on the Armed Services Committee, McCain and Lieberman had worked together on foreign and defense policy, but never on any environmental issue. McCain brought up the idea of a partnership on climate legislation. “He said to me as a friend, ‘You’ve been out there on this. And I’d like to sit with you, and your staff with my staff, and be more educated about why you really think it’s a problem and what could be done about it,'” Lieberman recalled. “So really that was all him. I give him a lot of credit.”

McCain and Lieberman unveiled their plan—an economy-wide cap-and-trade program based on the successful 1990 program for curbing acid rain pollution—in a colloquy they inserted into the Congressional record for August 3, 2001. “Deploying the power of a marketplace to pursue the least expensive answers is a unique and powerful American approach to the threat of climate change,” McCain said.

The September 11 attacks and their aftermath would delay their initiative, but they introduced their bill at a packed hearing (transcript) of McCain’s Senate Commerce Committee on January 8, 2003. McCain brushed aside those who focused on scientific uncertainties as a reason to delay action. “I prefer a more sound and scientific approach of starting with what is known or given and then proceeding to solve the problem at hand,” he said. McCain invoked National Academy of Sciences reports and recent research in what he said was “the longest opening statement I intend to give as chairman of this committee.”

“But we are talking about a very difficult, a very complex, and a very controversial issue, but one which I think is of the absolute most critical importance to the future of this nation and the world,” he said.

McCain-Lieberman: The Bipartisan Fight for Cap-and-Trade

McCain battled his party’s leaders over much of that year to bring the legislation to the floor. The Bush administration opposed mandatory carbon cuts, and Sen. James Inhofe (R-Okla.), the Senate’s most strident climate science denier, argued that any global warming legislation would have to go through his Environment and Public Works Committee, where it would surely die.

Meanwhile, the new Senate Majority Leader, Bill Frist (R-Tenn.), was struggling to advance a big energy bill as his first major legislation. Just before the August recess, he gained the support of Senate Minority Leader Tom Daschle (D-S.D.) to resurrect a prior energy bill that contained ethanol provisions important to Daschle’s home-state voters. All they needed was the unanimous consent of the Senate to bring back the bill that had passed the prior year; with both party leaders in favor, it should have been easy. But McCain and Lieberman would not agree.

Behind the scenes, they held up the energy bill for hours until they won an agreement for a floor vote on their Climate Stewardship Act. McCain “had the backbone and authority among his peers to just do it, and he really didn’t wilt,” recalls Tim Profeta, director of Duke University’s Nicholas Institute for Environmental Policy Solutions, who, as Lieberman’s lead staffer on the legislation, witnessed the tension over the showdown in the Senate cloakroom. “[McCain and Lieberman] both stood up against the leaders of their own parties to demand action on this issue.”

John McCain. Credit: Mark Wilson/Getty Images
McCain took on climate deniers in his words to Congress: “If I might quote the punch line from an old joke, ‘You can believe me or your lyin’ eyes.’ These are facts. These are facts that cannot be refuted by any scientist or any union or any special interest that is weighing in more heavily on this issue than any issue since we got into campaign finance reform.” Credit: Mark Wilson/Getty

On July 31, Frist announced that the McCain-Lieberman bill would not need to go through Inhofe’s committee, but would move directly to the floor. There would be six hours of debate, with no amendments allowed except McCain and Lieberman’s own revisions to the bill.

McCain insisted on a vote that was not just procedural, but actually on the substantive legislation on economy-wide carbon cap-and-trade, even if they couldn’t initially garner the 60 votes they needed. It was the same strategy McCain implemented successfully with Sen. Russ Feingold (D-Wis.) to drive bipartisan campaign finance reform through the Senate in 2002.

“His willingness to fight and get that vote is vintage John McCain,” said DesChamps. “Prior to a vote, it was easy for members to say, ‘I’m looking at it,’ and not really take a hard position on it. With the vote, you could have the conversation about what would it take to get them from a ‘no’ to a ‘yes’.”

Krupp said that altered the political landscape on climate. “Only when you find out where the politicians really stand can you have democracy functioning, and can you have progress on issues,” Krupp said. “Having the vote on McCain-Lieberman was the beginning of being able to explore which politicians were good on this issue and which weren’t.

“Obviously, it hasn’t yet resulted in getting a comprehensive climate bill through Congress, but it’s a big issue, kind of like the civil right issue,” Krupp said. “When we do get there, [McCain] will go down in history as someone who started that progress in a forceful way.”

McCain (lower right) with his squadron. Credit: Library of Congress
McCain (lower right), the son and grandson of Navy admirals, began his career as a naval aviator. During the Vietnam War, he was held as a POW for five and a half years after his plane was shot down. He retired from the Navy in 1981, was elected to the U.S. House in 1982, and served in the U.S. Senate from 1987 until his death in 2018. Credit: Library of Congress

Lieberman relishes the memory of the “classic, fiery McCain speeches” when the bill came to the Senate floor on October 29 and October 30, 2003.

McCain opened the session with a pre-emptive swipe at Inhofe’s plan to lead opposition to the bill by attacking the validity of climate science. “There are some scientists who will … say that pigs fly and up is down and black is white, but the majority opinion is that of the most respected body in America, the National Academy of Sciences, and they are the ones who come forward with the views that are corroborated by thousands of scientists all over America and the world,” McCain said. 

As their allotted six hours on the floor came to a close, McCain took the podium flanked by poster boards illustrating Arctic sea ice loss and the shrinking glacier on the summit of the largest mountain in Africa. He read the opening of Ernest Hemingway’s short story, “The Snows of Kilimanjaro,” and noted that the icy terrain the author described “may soon exist only in literature.” 

Again addressing the climate science deniers, McCain said, “If I might quote the punch line from an old joke, ‘You can believe me or your lyin’ eyes.’ These are facts. These are facts that cannot be refuted by any scientist or any union or any special interest that is weighing in more heavily on this issue than any issue since we got into campaign finance reform.” Gesturing to the map, he continued, “That is the Arctic Sea. That is the Arctic Sea. If you look at the red line, that is the boundary of it in 1979. Look at it now. You can believe me or your lyin’ eyes.”

Although McCain-Lieberman failed, 55-43, with 10 Democrats voting in opposition and two Democrats absent, the vote sent a ripple of hope through the community of climate activists. Five Republicans in addition to McCain—Lincoln Chafee of Rhode Island, Judd Gregg of New Hampshire, Susan Collins and Olympia Snowe of Maine, and Richard Lugar of Indiana—had supported the bill. And members of both parties who voted in opposition said they accepted climate science and pledged to work for a climate bill they could support—including the two who led the Senate vote in opposition to the Kyoto Protocol.

“We should recognize the efforts of Senators McCain and Lieberman and others on this particular issue,” said Sen. Chuck Hagel (R-Neb.) “Although I disagree with the approach they have proposed, I understand and share their concerns. It is important to keep the debate moving forward in order to develop and implement practical policies to deal with climate change.” Sen. Robert Byrd (D-W.Va.), said, “We owe it to our children and grandchildren to have the foresight to see that something is happening and to understand that we ought to do something about it soon.”

McCain and Lieberman made clear they planned to reintroduce the measure and seize what they saw as an opportunity to win converts. DesChamps recalls, “That vote in 2003 surprised a lot of people. At that point, it really hit the radar screen: ‘This could actually happen’.”

But that realization also brought out the opposition to climate legislation in full force. Business and fossil fuel interests joined in a new lobbying coalition focused on beating back environmental legislation, with McCain-Lieberman their primary focus. United for Jobs, led by Frontiers of Freedom, a nonprofit funded in part by the petrochemical billionaire Koch brothers, included the National Association of Manufacturers, the U.S. Chamber of Commerce and a slew of interest groups ostensibly dedicated to the aging population, workers and racial equality, but in fact funded by other Koch groups, Exxon and other fossil fuel interests.

Inhofe and others quoted studies they commissioned on how the climate legislation would wreck the economy. “A lot of Republicans, basically aided by the Chamber of Commerce, ran a very effective campaign in which they turned ‘cap and trade’ into ‘tax and trade’ and it got harder for people to support it,” Lieberman recalls. He and McCain reworked their bill and re-introduced it in the next Congress, but 2003 proved to be their high-water mark. In a 2005 vote, the measure failed 60-38.

McCain discusses climate change in Keene, New Hampshire, in 2007. Credit: McCain campaign

Still, climate action advocates had reason for hope in early 2008, after McCain advanced toward the Republican nomination for the presidency. With both Democratic contenders, Barack Obama and Hillary Clinton, on their side, it seemed no matter who won the presidency, there would be a strong supporter of a market-based climate change solution in the White House.

The GOP Nomination, and McCain’s Climate Pivot

In May 2008, a few weeks after McCain clinched the GOP nomination, he made what would be his last speech calling for climate action. In Portland, Oregon, at the North American headquarters of the Danish wind turbine manufacturer, Vestas, he predicted that one day such alternative energy companies “will change our economy forever.” But he said the government first had to create incentives to cut carbon emissions. “For all the good work of entrepreneurs and inventors in finding cleaner and better technologies, the fundamental incentives of the market are still on the side of carbon-based energy,” he said. “This has to change before we can make the decisive shift away from fossil fuels.” 

Highlights of the Vestas speech in 2008. Credit: McCain campaign

But McCain, the presidential candidate, was calling for less ambitious cap-and-trade legislation than the bill that McCain, the senator, had co-sponsored with Lieberman. His new goal was 60 percent below 1990 levels by 2050, instead of 70 percent. And he signaled a further retreat at a news conference a few weeks later, when he suggested—in contradiction of his previous stand—that his plan was for emissions targets, not required cuts. “I would not … impose a mandatory cap at this time,” he said. He could see that the run-up in global oil prices would dominate political debate throughout the summer.  

Over the next few weeks, U.S. gasoline prices climbed above $4 a gallon for the first time ever—even in inflation-adjusted terms, the hit to consumers surpassed the previous peak during the Iran-Iraq war in 1980. McCain sounded more and more in step with Republican party leaders who saw a ramp-up in oil and gas production as the solution to the nation’s energy woes. Chants of “Drill, Baby, Drill” would reverberate at their convention.

McCain came out in support of expanded offshore drilling, and in the meantime, he called for suspension of the 18.4-cents-per-gallon federal excise tax on gasoline, a summer “holiday” that contravened economic wisdom by addressing tight supply with low prices.

John McCain. Credit: Mark Wilson/Getty Images
As the 2008 Republican presidential nominee, McCain came out in support of expanded offshore drilling and called for suspending the federal gas tax. “Drill, baby, drill” became a common chant among his supporters during the campaign. Credit: Mark Wilson/Getty Images

McCain even refused to support the revamped cap-and-trade bill that Lieberman, by now an Independent, brought to the floor with Sen. John Warner (R-Va.) as co-sponsor. McCain, who complained the bill had insufficient nuclear energy incentives, was one of 16 senators (along with Obama, Clinton and Biden) absent for the 48-36 vote, The measure fell 12 votes short of the 60 needed for passage.

By this time, many climate activists were looking ahead to 2009 as the year to advance climate legislation. A president they could bank on to sign climate legislation, they hoped, would be in the White House, and McCain’s seeming softening on their cause gave them impetus to choose a favorite; soon after Clinton conceded to Obama in June, the Democrat was endorsed by major environmental groups like Sierra Club and the League of Conservation Voters. Former vice president Gore, by then an icon in the movement due to An Inconvenient Truth, delivered what seemed like a eulogy for McCain’s career as a leader on climate policy when he introduced Obama on the final night of the Democratic convention. “In spite of John McCain’s past record of open-mindedness on the climate crisis, he has apparently now allowed his party to browbeat him into abandoning his support of mandatory caps on global warming pollution,” Gore said.

That same day, McCain had announced that his running mate would be Alaska Gov. Sarah Palin. In naming Palin, McCain was giving in to advisers who feared his preferred choice—Lieberman—would alienate the Republican base. It is a choice McCain later said he regretted. But the decision was in sync with the growing political polarization over climate change.

John McCain and Sarah Palin. Credit: Darren Hauck/Getty Images
McCain followed his advisers’ recommendation in choosing then-Alaska Gov. Sarah Palin as his running mate in 2008. They feared his preferred choice—Lieberman—would alienate the Republican base. Credit: Darren Hauck/Getty Images

McCain never renounced his belief in climate science or the need for action, but after he lost the presidency, he never resumed his role as a leader in the drive for climate legislation. When climate change legislation sponsored by Rep. Henry Waxman (D-Calif.) and Rep. Edward Markey (D-Mass.) passed the House in 2009, McCain called it a “farce” in an interview with The Wall Street Journal. “They bought every industry off—steel mills, agriculture, utilities,” he said. “I would not only not vote for it. I am opposed to it entirely, because it does damage to those of us who believe that we need to act in a rational fashion about climate change.”

But McCain did not work in the Senate to come up with a different plan. He left that task to his old partner, Lieberman, as well as another friend, Sen. Lindsey Graham (R-S.C.), and Sen. John Kerry (D-Mass.). “I remember John said to me, ‘I’ve been with you three times on it. I agree with it. It just feels to me like it’s not going anywhere. I’m going to focus on some other things,'” Lieberman now recalls. “Lindsey, our third amigo—I always felt that John encouraged him to join with me and John Kerry.”

Lindsey Graham whispers with John McCain. Credit: Win McNamee/Getty Images
After he lost the presidency, McCain never resumed his role as a leader for climate legislation. His friend Sen. Lindsey Graham took up that role instead, and Lieberman said he believed McCain urged Graham to do so. Credit: Win McNamee/Getty Images

No climate bill made it to the Senate floor. The Obama White House, which focused on a giant economic stimulus package and health care reform at the start of the administration, never made a big push on the climate bill in the Senate. In the wake of the economic collapse of 2008, even supporters of climate action were wary of a market-based cap-and-trade solution. And lobbying was fierce, not only for and against the bill, but by industries seeking carve-outs and special treatment. Between 2003—the year of the first vote on McCain-Lieberman—and the beginning of the Obama administration, the number of registered lobbyists focused on climate change reached 2,340—a 300 percent increase in just five years.

Views differ among climate activists on why McCain abandoned the battle for U.S. climate legislation at its most crucial moment, but all agree that the nature of the fight had changed.

Some believe that cap-and-trade legislation was taking a much different shape than the solution that McCain had championed. “McCain-Lieberman tried not to have much government intervention, aside from the fundamental notion that we need to put a lid on greenhouse gases and let the market figure out how to do that,” said Roy, who had helped put together a business-environmental group coalition to push cap-and-trade. Instead, the legislation that had emerged from the Democratic-controlled House auctioned off carbon pollution allowances to create a revenue stream that would be recycled back into the economy. “In my view,” said Profeta, “he saw the issue in 2009 had crept too far from the mission of climate change, and was too much becoming a vehicle through with other Democratic priorities were being pushed.”

But also important was what was happening back in Arizona in 2009 and 2010—McCain was facing his first serious primary challenge from the right. Although McCain would hold on to his Senate seat, his opponent, radio talk show host and Tea Party-oriented former Congressman J.D. Hayworth, spent the year castigating him for his past stance on climate change, while McCain kept silent on the subject. One of Hayworth’s financial backers was the conservative group Citizens United, which earlier that year won a case at the Supreme Court paving the way to unlimited federal campaign contributions. Although Citizens United would lose its effort to unseat McCain, it erased part of McCain’s legacy, striking down part of the landmark 2002 campaign finance reform he had co-authored. Some say it also knocked McCain out of the climate fight.

John McCain. Credit: Win McNamee/Getty Images
In 2017, McCain fought for climate policies again when, in defiance of the Trump administration, he cast the deciding vote against repeal of regulations on the potent greenhouse gas methane. Credit: Win McNamee/Getty Images

“There’s no sugar-coating the fact that he shelved his leadership role on climate for a while,” said Curtis. “But instead of blaming John McCain for walking away from an issue and not showing up, we should be saying ‘holy crap, something profound has happened with the Republican Party,’” Curtis said. “It’s something much more fundamental about the role of money in politics. And in order for our issue to prevail, we have to deal with the larger issue first.”

Kalee Kreider, Gore’s former communications director and environmental adviser, still sees McCain as a hero of the climate movement. “One of the very honorable things about Sen. McCain is he evolved his position on climate,” she said. “He was pressed about it, he learned about it, and he developed an educated position on it, and fought for it. For that, he should be commended. Nothing subsequent to that can ever take away from what he did for the issue as a public servant.”

“What also makes what he did unusual is that he never got a bonus from it,” Kreider said. “He was never going to be rewarded politically, either with financial donations or with a ton of votes in Arizona.”

A kind of coda to McCain’s climate story came on May 10, 2017, when in defiance of the Trump administration, he cast the deciding vote against Congressional repeal of Obama administration regulations on the potent greenhouse gas methane. McCain can be seen on the floor facing off heatedly against a half-dozen GOP senators who surround and block him before he gestures thumbs-down, a foreshadowing of his later decisive vote against the Obamacare repeal. McCain said in a statement that while he thought the Obama methane rule was “onerous,” he objected to the GOP’s use of a legal provision that would have forever blocked the Interior Department from future regulation of methane, which he said was “an important public health and air quality issue.”

“They all knew what his position was and thought they could turn him,” said Jeremy Symons, EDF’s vice president of political affairs. “The fact that he stood tall made a huge difference.  That moment, that day demonstrated that environmental issues are always going to be a fight. And since then, the Senate has been a firewall” against the effort to roll back environmental protection in the current Congress.

That defensive victory is a long way from the Congressional win that climate activists once thought that McCain-Lieberman had put within reach. Enough years have passed to see that the modest goals of that legislation could have been achieved without wrecking the economy. U.S. emissions in 2010 were 4 percent below those of 2000, the McCain-Lieberman goal, while in terms of real GDP the economy had grown 18 percent. And in 2016, U.S. greenhouse gas emissions were just 2 percent higher than the legislation’s goal—1990 levels—while the economy was 90 percent larger in inflation-adjusted terms.

Profeta believes that McCain’s greatest climate legacy is not in the legislation that lost, but in the broadening of the movement he showed was possible. “McCain’s efforts began to bring different stakeholders together,” said Profeta. “They haven’t been able to overcome the tribalism of Washington, D.C., politics, but when we see major corporations, national security and religious groups coming together on this issue—that base of political support is still there,” he said.

In Krupp’s view, McCain stood for a principal that will be crucial to the future of the fight for U.S. climate action. “There is a way that we can preserve freedom of choice, using markets, taking advantage of business’ ingenuity, very consistent with American values and American freedom, but it involves coming up with a bipartisan solution,” said Krupp. “I would just say we need more to follow in his footsteps now, and show leadership, and bring back the hope of the McCain-Lieberman days.”