The 95-0 Byrd-Hagel Vote That Doomed Kyoto in the Senate

On July 25, 1997, the United States Senate did something it almost never does on a contested issue: it agreed with itself completely. The roll call on Senate Resolution 98 came back 95 to 0. Every liberal Democrat who voted, every conservative Republican, the senators from coal country and the senators from California and New England, all said yes. The resolution had no force of law. It was a sense-of-the-Senate statement, the kind of thing the chamber passes to send a message. But the message was aimed at a negotiation set to begin in Kyoto, Japan, that December, where the world's governments would try to write the first binding limits on greenhouse gases. The Senate told President Bill Clinton that it would not accept any treaty that required the United States to cut emissions unless developing countries took on obligations too, or any treaty that would seriously harm the American economy. The two sponsors were Robert Byrd of West Virginia, a Democrat and the Senate's great defender of its own powers and of coal miners, and Chuck Hagel of Nebraska, a first-term Republican who would later serve as a Democratic president's secretary of defense. Their resolution was so short that it fit on a few pages. Its effect lasted decades.

In short: The 1997 Byrd-Hagel resolution, passed 95 to 0, warned that the Senate would reject any climate treaty that bound wealthy nations but not developing ones. The Kyoto Protocol did exactly that, and no president ever sent it to the Senate. The vote shaped every US climate agreement since, which is why the Paris Agreement was designed so that it would not need Senate approval at all.

The bargain struck in Berlin

To understand why the Senate was alarmed, start two years earlier. In 1995, at the first conference of the countries that had signed the 1992 United Nations climate treaty, negotiators met in Berlin and agreed on a mandate for the next round of talks. The Berlin Mandate said that the new commitments would apply to the industrialized countries listed in the treaty's first annex, the wealthy nations and the former Soviet bloc, and not to developing nations.

The logic was rooted in fairness. Rich countries had produced most of the carbon dioxide then in the atmosphere, and they had grown rich doing it. Developing countries argued that it would be unjust to ask them to limit emissions before they had lifted their people out of poverty. The treaty itself spoke of common but differentiated responsibilities. The United States, under Clinton, had agreed to the Berlin Mandate.

But the world was changing quickly. China's economy was growing at a pace that would soon make it one of the largest emitters on Earth. In the Senate, the idea that the United States would accept binding limits while China, India, Brazil and others did not looked like a recipe for moving factories and jobs overseas while making little difference to the global total.

What the resolution said

The resolution itself was simple. It said the United States should not sign any protocol or agreement that would mandate new commitments to limit or reduce greenhouse gas emissions for the industrialized nations unless the agreement also mandated new specific scheduled commitments for developing nations within the same compliance period, or that would result in serious harm to the economy of the United States. It also asked that any treaty sent to the Senate come with an explanation of the legislation needed to carry it out and an analysis of its economic costs.

Senators who supported the treaty process voted for it anyway. Some genuinely agreed with its premise. Others saw it as a way to strengthen the American hand in Kyoto, telling the other side that the Senate would not accept a lopsided deal. Some simply did not want to be on the record against protecting American jobs. John Kerry voted yes; so did the Senate's most committed environmentalists. Byrd's influence as a senior appropriator and his long defense of coal miners in West Virginia mattered too. The unanimity made the message impossible to misread.

Kyoto, and the treaty that never came home

In December 1997, the parties met in Kyoto. Vice President Al Gore flew in near the end and helped broker a final deal. The Kyoto Protocol set binding emission targets for industrialized countries, with the United States pledging to cut its emissions to 7 percent below 1990 levels during the first commitment period, from 2008 to 2012. Developing countries took on no binding targets.

By the terms of the Byrd-Hagel resolution, the agreement failed the test on its first page. The United States signed the protocol in November 1998, a symbolic act, but Clinton never submitted it to the Senate, where treaties require a two-thirds vote. The votes were not there and everyone knew it. In March 2001, President George W. Bush announced that the United States would not implement Kyoto, citing the exemption for developing countries and the cost to the economy. Kyoto took effect in 2005 without the United States, after Russia ratified it.

Without the largest economy on board, Kyoto's record was mixed. The European Union took its targets seriously, built the world's first large carbon market in 2005 to meet them, and as a bloc met its first-period commitment. Canada ratified the protocol, saw its emissions climb with the growth of oil sands production, and withdrew in 2011. Global emissions kept rising throughout, driven largely by fast-growing economies that had no binding targets under the agreement. Critics of the protocol on both left and right have read that record as proof that its design was flawed from the start: too narrow, too top-down, too easy for big emitters to ignore. Its defenders answer that it built the reporting systems, carbon markets and habits of cooperation that later agreements relied on.

The case for Byrd and Hagel

It is worth pausing to take the senators' argument seriously, because many progressives have treated the vote as simple obstruction. It was not only that.

The senators' concern about developing countries was prescient in one sense. China passed the United States as the world's largest annual emitter of carbon dioxide in the mid-2000s, and its emissions have since grown to far more than America's. A treaty that left out the fastest-growing emitters could not by itself solve the problem it addressed. And the worry about jobs was real to the people the senators represented. Coal communities in West Virginia, Kentucky and Wyoming had good reason to fear policies written in faraway capitals.

The answer progressives should give is not that those concerns were wrong but that they were not the whole story. The wealthy countries had caused most of the warming to that point and had the money and technology to lead; developing nations were never going to accept limits before the countries that created the problem showed they were serious. By refusing to go first, the United States gave other big emitters a reason to wait as well. And the economic harm the resolution feared was often overstated: clean energy has since become the cheapest source of new power in much of the world. Coal's decline in the United States since the 2000s was driven largely by cheap natural gas, not by a treaty.

How one vote shaped Paris

The more lasting effect of Byrd-Hagel was on the design of every agreement that followed. American negotiators came to believe that no climate treaty with binding emission cuts could ever pass the Senate. So they changed the shape of the agreements.

The 2009 talks in Copenhagen ended without a binding treaty, but they produced pledges from both rich and developing countries, including China and India. The Paris Agreement of 2015 completed that shift. Every country, rich and poor, set its own target, called a nationally determined contribution. The targets themselves are not legally binding; what is binding is the obligation to report, review and update them. The Obama administration treated Paris as an executive agreement under the existing 1992 treaty, which the Senate had already approved, so it did not need a new two-thirds vote.

That design solved the Byrd-Hagel problem: developing countries now had commitments, and the Senate was bypassed. But it came at a cost. An agreement that one president can join on his own authority, another can leave on his own. President Trump announced withdrawal from Paris in 2017, and it took effect in November 2020. President Joe Biden rejoined in 2021. In January 2025, on his first day back in office, Trump ordered the United States out again, and that withdrawal took effect a year later. The country has gone in and out of the world's main climate agreement like a revolving door, and other nations have learned to discount American promises accordingly.

The treaty the Senate did ratify, unanimously

There is a useful counterexample, and it involves the same chamber and the same atmosphere. In 1987, nations meeting in Montreal agreed to phase out the chemicals that were destroying the ozone layer, the thin band of the upper atmosphere that shields life from ultraviolet radiation. The evidence had come from scientists who linked chlorofluorocarbons, used in refrigerators, air conditioners and spray cans, to ozone loss, and from the discovery of a seasonal hole in the ozone over Antarctica. The Reagan administration, not known for its enthusiasm for regulation, helped lead the negotiations. In 1988, the Senate ratified the Montreal Protocol by a vote of 83 to 0.

Why did ozone succeed where carbon failed? Several reasons stand out. The number of companies making the chemicals was small, and substitutes were becoming available, so the costs were limited and predictable. American manufacturers saw a market for the replacements. The treaty included developing countries, giving them more time and a fund to help them make the switch, which answered the fairness objection without exempting them. And the danger, skin cancer, was personal and easy to explain.

The story continued into the present. In 2016, nations agreed to the Kigali Amendment to the protocol, phasing down hydrofluorocarbons, the replacement chemicals that turned out to be powerful greenhouse gases. American manufacturers supported it because they had products ready to sell. In September 2022, the Senate ratified the Kigali Amendment by 69 to 27, with a substantial number of Republicans voting yes. A climate treaty, ratified by two-thirds of the Senate, in a deeply divided era. It can be done, when the economic interests line up and the design answers the objections. That is a more useful lesson than the one usually drawn from 1997.

Byrd's second thoughts

The senator who gave the 1997 resolution his name did not stand still. Robert Byrd spent his career defending coal, and he remained a defender of the miners he represented. But near the end of his long life, he spoke more bluntly about where the industry was headed. In late 2009, as the debate over cap-and-trade raged, he issued a statement telling West Virginians, in substance, that the demand for coal was declining, that denying climate change would not save mining jobs, and that the state's future depended on embracing new technology rather than resisting change. He died in 2010, the longest-serving senator in American history up to that time.

His shift does not erase the resolution. It does suggest that the politics of energy are not fixed, and that leaders from fossil fuel states can change their minds when they see the economics change around them.

The Senate is still the gate

The deeper lesson is about the Senate itself. Treaties need two-thirds of senators present; even ordinary climate laws have long needed sixty votes to break a filibuster, unless they can be passed through budget reconciliation with a simple majority. That is why the major climate law of 2022, the Inflation Reduction Act, was written as a budget bill of tax credits and spending, and why it passed with only Democratic votes. And it is why much of it could be rolled back the same way in 2025.

Progressives have sometimes wished the Senate away. A better approach is to build the kind of support that can survive it. Byrd-Hagel passed unanimously because senators from both parties saw political risk only on one side of the vote. Changing that means building climate policy that delivers visible benefits, factories, jobs, lower bills and cleaner air, to the states whose senators hold the deciding votes. It means treating coal and oil communities as partners with a stake in the transition. And it means pointing to the votes that already cross the aisle, such as bipartisan support for nuclear power, grid improvements and some clean energy credits, as the foundation for more.

What you can do

• See where the parties already agree. Our page of bills passed by both parties together shows what can clear Congress with support from each side, a useful map for any lasting climate deal.
• Tell your senators which vote you want. Find your two senators through the representatives search and ask whether they would support climate legislation that funds jobs and new industry in your state.
• Follow the new majority. The incoming Congress will set its own climate agenda; our page on Democrats in Congress follows what members are proposing and what can actually pass.
• Keep the larger picture. The climate policy page collects reporting on global talks, American commitments and what other countries are doing while Washington debates.