Since at least 1991, the United States of America has been considered a global hegemon; a powerful, international trend-setter. It’s domestic affairs are as important to the world stage as it’s worldwide commitments.
Despite this, the US has a complex and often difficult relationship with environmental regulation and the mitigation of climate change. Further complicated by the re-election of President Donald Trump, the future of American climate policy may again be hanging in the balance.
In this article, we examine the highs and lows of America’s history with environmental and climate change law since the 1970s to place in context current and unfolding developments in US environmental policy.
The 1970s: Stepping Up to the Plate
As the implications of climate change and the need for more tangible environmental regulation emerged in many countries from the late 1960s, the USA was one of the first to begin to transform its environmental policy in line with developing scientific and climate predictions.
The year 1970 marked the beginning of American leadership in climate policy.
On 1 January 1970, President Richard Nixon signed the National Environmental Policy Act (NEPA) which ensured that government organisations were required to assess potential environmental damage when considering policy objectives and making decisions. This was a huge step in the right direction, as numerous ecological disasters, particularly the highly-publicised Cuyahoga River Fire in November 1969 in Cleveland, Ohio, prompted calls from scientists and activists alike for politicians to impose serious regulations on the way companies and organisations interacted with the natural environment.
Although preceded by the Air Pollution Control Act 1955 and the Clean Air Act 1963, the Clean Air Act 1970 fundamentally altered the way in which the US federal government approached air quality and pollution control. It set down four regulatory initiatives to limit emissions from transportation and industrial sources on the federal and state levels:
- the National Ambient Air Quality Standards (NAAQS); defined clean air and set out the quantity of pollution required to infringe on public health.
- State Implementation Plans (SIPs); required individual states to enforce the NAAQS.
- New Source Performance Standards (NSPS); ensured that industries utilise emission control technologies as they modernise their operations or machinery.
- National Emission Standards for Hazardous Air Pollutants (NESHAPs); imposed standards upon pollutants which are known to cause serious harm to public health.
These comprehensive regulations on air pollution were significant in laying the groundwork for future regulation, transforming the role of the federal government in climate policy, and responding to developments in scientific research which warned of severe global environmental problems arising from sustained air pollution.
1970 also witnessed the establishment of the Environmental Protection Agency (EPA), founded on 2 December 1970 to enforce federal climate policy objectives. Along with this, the EPA would;
- Monitor the condition of the environment
- Set and enforce standards of air and water quality, cooperating with each state
- Develop and pursue its own environmental pollution control initiatives
- Perform its own research into pollutants and their impacts on the environment
Thus, during the 1970s the United States was willing to step up to be a global leader in climate consciousness and environmental regulation, exemplified particularly by the passing of the NEPA and Clean Air Act 1970, and the formation of the EPA – decisions which would influence numerous governments around the world to adopt similar policies.
The 1980s: Towards Global Leadership
Into the 1980s, the United States continued to lead in the way of climate regulation.
The US played a central position in negotiating the Montreal Protocol in 1987, potentially one of the most successful environmental treaties ever made. With ratifications from 198 countries including every United Nations (UN) member state, the Protocol committed to limiting and phasing-out the use of hydrochlorofluorocarbons (HCFCs) which had been shown to be depleting the Ozone layer, made particularly relevant two years prior at the Vienna Convention in 1985.
According to the UN Environment Programme (UNEP), without the 1987 Montreal Protocol, Earth’s fragile Ozone layer would have depleted tenfold by 2050. Thus the Protocol resulted in tangible positive impacts for human health, reducing potential cases of skin cancers and eye cateracts all over the world. It is estimated that by 2030, the Protocol’s impacts on Ozone preservation will have saved 2 million people each year from skin cancer. Hence, the Montreal Protocol enabled the US to further position itself as a global leader in recognising and seeking to mitigate climate change, global warming, and environmental harm on the global stage.
Further, in a huge step for international environmental law, the US played a vital role in the creation of the Intergovernmental Panel on Climate Change (IPCC) in Geneva, Switzerland in 1988. The IPCC is a UN-affiliated body responsible for assessing the academic scientific literature and research on climate change, producing neutral and policy-relevant reports on this research.
With the UN being headquartered in New York City, USA, the UN-affiliated IPCC signified the central, influential position of the US on global environmental governance and climate change research initiatives. America’s integral role in forming the IPCC in 1988 reflected its growing leadership in international and environmental law, and in shaping scientific climate change consensus on a global scale. Thanks to US involvement and commitment, the IPCC marked a historically unprecedented turning point in international climate cooperation.
The 1990s: Cracks in Climate Leadership
While the 1990s witnessed significant efforts by the US to continue its trajectory as a global leader on climate change and environmental law, the decade was also marked by considerable setbacks and political division concerning US climate policy.
Positively, 1992 saw the US sign the United Nations Framework Convention on Climate Change (UNFCCC) at the Earth Summit in Rio de Janeiro, Brazil. Coming into force in 1994, it committed the 198 signatory countries to voluntary, non-binding reductions in greenhouse gas emissions. Due to there being far less scientific evidence of climate change than there is now, the UNFCCC relied on the key developments in generating international environmental consensus of the Montreal Protocol.
By 1995, the commitments of the UNFCCC were vindicated by the publication of the IPCC’s Second Assessment Report. This had the effect of reinforcing the scientific consensus on climate change and global warming, and considerably influenced international negotiations on the topic, and helped paved the way towards binding emission targets.
1997 served as a decisive year for global commitments to climate change mitigation, yet a major setback in American climate leadership. On one hand, the US played a vital role in the creation and negotiation of the Kyoto Protocol, initially appearing to establish itself as a nation-state willing to wholly commit to the binding targets which the Protocol set down.
However, beset by domestic political division and despite support from President Bill Clinton, the US failed to ratify the Kyoto Protocol. Although it was a founding signatory of the UNFCCC, the Byrd-Hagel Resolution, passed by the US Senate 95-0, declared that the US would not ratify the Kyoto Protocol. It argued that the Protocol unfairly exempted developing countries, particularly China and India, from the binding emission reduction targets. Thus, despite President Clinton signing the treaty, it was unable to enter American law due to the unilateral objection from the Senate.
A severe setback in American climate leadership, the refusal to ratify the Kyoto Protocol stained the country’s track record of commitment to mitigating global warming and established a devastating precedent that it was at the liberty of nation-states to reject international treaties, especially those which concern endeavours to combat worldwide environmental deterioration. In retrospect, the Byrd-Hagel Resolution represented a turning point in an American commitment to international environmental law and climate change regulation.
The 2000s: Setback After Setback
The American setback at Kyoto would fail to be an anomalous one, as the 2000s proved to be a difficult decade for US climate leadership.
While President Clinton had supported and signed the Kyoto Protocol in 1997, his successor President George W. Bush formally rejected it, citing much of the same reasoning as the Byrd-Hagel Resolution – particularly the exemption of developing countries from binding emissions targets and the potential harm to the US economy. These two events began the gradual deterioration of US credibility in international climate diplomacy, breaking down American leadership.
In the 2000s, many of the American failures to commit to climate protection occurred on the domestic rather than the international scene, as the US became entangled in numerous foreign conflicts in the wake of the 9/11 terrorist attacks and the subsequent War on Terror. In 2003, the US Senate shot down the proposed Climate Stewardship Act, informally known as the McCain-Lieberman Bill, which proposed a ‘cap-and-trade’ system for carbon emissions.
Further, in 2006, the aforementioned EPA rejected a petition calling on them to regulate carbon dioxide emissions from motor vehicles, claiming that this was not covered by the Clean Air Act.
Although the subsequent Massachusetts v. EPA (2007) saw the US Supreme Court rule that the EPA could not refuse and in fact did have the authority to regulate carbon dioxide emissions, the reluctance of the EPA to do so initially reflected underlying problems concerning an American hesitancy to commit to climate change and environmental protection initiatives.
While George W. Bush’s presidency ended in 2009, the administration of Barack Obama was equally fraught with climate failures and missed opportunities to reinstate American climate leadership, albeit it heralded a significant improvement as the USA marched towards the end of a decade plagued by fossil fuel and heavy industry lobbyists and failed federal climate regulations.
Negatively, 2009 witnessed the failure of the American Clean Energy and Security Act to make it to the Senate due to Republican and moderate Democrat opposition. Informally known as the Waxman-Markey Bill, the Democrat-proposed bill sought to implement an ever-elusive cap-and-trade system and limit overall carbon dioxide emissions. An early setback for Obama’s administration, but it did not prove to be the nail in the coffin for efforts to maintain American climate leadership.
The 2010s: Highs and Lows
During Obama’s second term as president, he launched the Clean Power Plan in August 2015. It sought to limit the carbon emissions of American power plants in a landmark effort return the US to climate trend-setting. It established enforceable emission limits and sought to accelerate a transition from fossil fuels to renewable energy in the US energy market. Later, in 2016, the Obama administration passed the American Recovery and Reinvestment Act which encouraged huge investment into renewable energy technologies via financial provisions and tax incentives in excess of $90 billion.
Most infamously, in December 2015 Barack Obama signed the Paris Climate Agreement at the COP21 UN Climate Change Conference in Paris, France. Obama was centrally involved in negotiating the Agreement, marking a return to global leadership in the climate arena for the US and expressed an American willingness to commit to legally binding emissions targets. The 196 signatories sought to ensure that the global temperature did not increase beyond 1.5°C above pre-industrial levels. This symbolised a renewed ambition for the USA to remain a leader in international climate diplomacy, committing to reduce carbon emissions to 26-28% below 2005 levels by 2025.
The 2016 Presidential Election resulted in the election of President Donald Trump to his first term in office. Soon into his presidency, Trump took an adversarial stance to renewed efforts to bring the US back to the forefront of international climate diplomacy. In 2017 made the reactionary decision to withdraw the US from the Paris Agreement less than two years after it led its negotiations. This was particularly easy for Trump because Obama had chosen not to seek ratification of the Agreement from the Senate, allowing his successor to withdraw from it with considerably less hurdles than there would have been otherwise.
The decision to withdraw from the Paris Agreement in 2017 rendered the US the only country in the world to do so, and represented a devastating blow to international climate cooperation, American leadership on the world stage, and global climate change consensus.
From the outset, Trump expressed consistent skepticism regarding the accuracy of climate science and existence of global warming, and showed a reluctance, and often explicit refusal, to engage with environmental regulation and climate change initiatives.
In 2019, the Trump administration repealed Obama’s Clean Power Plan. This was partially enabled by the cooperation of EPA Administrator Andrew Wheeler – a Trump ally and former fossil fuel lobbyist – returning to the institutional limitations of the EPA and an increasing track record of negligence of its core objectives. Further, by January 2021 the Trump administration was pushing forward its drive to lease land within the Arctic National Wildlife Refuge (ANWR) in Alaska to drill for oil, motivated by the reserve’s proximity to lucrative oil deposits at the nearby Prudhoe Bay.
Consequently, any headway made by American legislators towards a renewed global climate leadership was haunted by subsequent setbacks and U-turns by the Trump administration towards the end of the decade, effectively destroying much of what remained of US climate credibility when it comes to policy.
The 2020s: The Biden Administration
The Presidential Election in 2020 witnessed the election of President Joe Biden, the former vice-president and close ally to Barack Obama. The Biden administration has since come to represent a last-ditch effort to undo the damage done by the preceding Trump administration and an attempt to renew American climate leadership and bring it into the new decade.
To show off his progressive attitude to climate change and commitment to undoing the damage of the Trump administration, one of the first major decisions made by the Biden administration was to rejoin the Paris Agreement, which they did in 2021. In a step-up from Obama’s initial commitment to the Agreement, Biden pledged that the US would reduce its carbon emissions to 50-52% below 2005 levels by 2030. This marked what would become an apparently fleeting return to credibility for American policymakers regarding climate diplomacy.
In a landmark show of commitment to climate change mitigation, the Biden administration passed the Inflation Reduction Act (IRA) in 2022. Pledging $369 billion in grants, subsidies, loans, and tax reductions, the IRA represented the largest investment in renewable energy in American history, and is projected to reduce carbon emissions to 40% below 2005 levels by 2030, reaffirming American commitment to combatting climate change and upholding its Paris Agreement pledges.
Such a monumental act reinforced the environmental ambitions of the Biden administration and reassured the rest of the world that the climate blunders of the Trump administration were not going to be repeated.
The 2020s Continued: The Trump Administration
Since re-entering the White House in January 2025, Trump has already set in motion a number of initiatives to dismantle the attempts made by the Biden administration to salvage American climate policy and tear the US further from its former position as a global leader in climate action.
On 20 January, Trump signed an Executive Order titled ‘Putting America First In International Environmental Agreements’ to withdraw the US from the Paris Agreement for the second time, taking the US away from the international consensus and deteriorating US climate credibility – again. Along these lines, on 4 March, Trump ordered the withdrawal of the US from the UN Loss and Damage Fund, an organisation set up to provide aid to poor countries suffering from the impacts of climate change.
Revisiting institutional concerns surrounding the EPA, a number of developments have occurred to contradict its official role. The new and current Administrator of the EPA, Lee Zeldin – a close ally of Trump – is indicative of the administration’s broad anti-environmental, deregulatory agenda. Under Zeldin, the EPA has already proposed the suspension of 31 regulatory measures for the protection of nature and the climate, marking the self-proclaimed ‘biggest deregulatory action in US history.’ Further, on 12 March, the Trump administration announced that it would consider scrapping the EPA’s 2009 Endangerment Finding, which concluded that certain greenhouse gases, such as carbon dioxide, methane, and sulphur hexafluoride, pose a threat to human health.
In less than three months, the second Trump administration has so far dealt significant damage to climate protection initiatives inside the USA and killed off whatever remained of American global climate leadership. It remains to be seen what else the new president has in store for US climate policy.
Conclusion
The US has a complicated history with climate policy.
Despite being at the forefront of responding to scientific developments regarding climate change in the 1970s and 1980s, by the end of the 1990s the US was beginning to show itself as hostile to binding international commitments to climate targets, such as the Kyoto Protocol.
The 2000s showed that US lawmakers had also become reluctant to introduce modernising pollution control legislation, rejecting numerous proposals to the benefit of fossil fuel companies and lobbyists.
The early 2010s saw a renewed drive to catapult the US back into international climate leadership, particularly via the Paris Agreement in 2015. Yet the subsequent Trump administration began to dismantle much of what the Obama administration had done to rebuild American climate credibility, withdrawing from the Paris Agreement and opening up vast swathes of Alaskan land for oil drilling.
The attempts made by the Biden administration to reassure the world of America’s climate commitments notwithstanding – such as the rejoining of the Paris Agreement in 2021 – it’s efforts have since been overshadowed by recent rollbacks under the second Trump administration since January 2025. The US has withdrawn from the Paris Agreement for a second time, and pro-Trump institutional support within environmental regulatory bodies like the EPA pose challenges for the future of domestic pollution control and climate protection in America.
It is evident that since 1970, the extent to which the US has been committed to a progressive climate policy has depended heavily on the incumbent president and party, although this has not always been so clear-cut. While this is seen most obviously in the contrasting policy objectives of George W. Bush and Barack Obama, or Donald Trump and Joe Biden, it is less clear in cases like that of Republican Richard Nixon and his pursuit of transformative environmental policies in the 1970s, and that of Bill Clinton whose support for the Kyoto Protocol was undermined by lawmakers in the US Senate.
What is clear is that climate policy has proved to be volatile in recent American history. The US has jumped back and forth between international climate leadership and scientific consensus on one hand, and fossil-fuel isolationism and climate change denial on the other.
In various ways, the US has succeeded and failed in furthering environmental policy in the way of climate change mitigation, and has influenced the policies of other countries in positive and negative directions.
Donald Trump is unlikely to acquiesce to climate activists or backtrack on his environmental policy moves, and it is certain that the question of US commitment to climate change prevention will continue to permeate American politics and fuel heated debate.
For those who seek positive change, activism and resistance is the way forward, as the enduring health of the planet is put at greater risk the longer climate commitments are snuffed out and pledges are ignored.