The climate change policy of the United States has major impacts on global climate change and global climate change mitigation. This is because the United States is the second largest emitter of greenhouse gasses in the world after China, and is among the countries with the highest greenhouse gas emissions per person in the world. Cumulatively, the United States has emitted over a trillion metric tons of greenhouse gases, more than any country in the world.
Climate change policy is developed at the state and federal levels of government. The Environmental Protection Agency (EPA) defines climate change as "any significant change in the measures of climate lasting for an extended period of time." Essentially, climate change includes major changes in temperature, precipitation, or wind patterns, as well as other effects, that occur over several decades or longer. The policy with the biggest US investment in climate change mitigation is the Inflation Reduction Act of 2022.
The politics of climate change have polarized certain political parties and other organizations. The Democratic Party advocates for an expansion of climate change mitigation policies whereas the Republican Party tends to advocate for slower change, inaction, or reversal of existing climate change mitigation policies. In 2025, the second Trump administration promoted climate change denial and misinformation and moved to undo the regulation of greenhouse gases under the Clean Air Act.
Most lobbying on climate policy in the United States is done by corporations that are publicly opposed to reducing carbon emissions.
Federal policy
International law The United States, although a signatory to the Kyoto Protocol, has neither ratified nor withdrawn from the protocol. In 1997, the US Senate voted unanimously under the Byrd–Hagel Resolution that it was not the sense of the Senate that the United States should be a signatory to the Kyoto Protocol. In 2001, former National Security Adviser Condoleezza Rice, stated that the Protocol "is not acceptable to the Administration or Congress".
In October 2003, the Pentagon published a report titled An Abrupt Climate Change Scenario and Its Implications for United States National Security by Peter Schwartz and Doug Randall. The authors conclude by stating, "this report suggests that, because of the potentially dire consequences, the risk of abrupt climate change, although uncertain and quite possibly small, should be elevated beyond a scientific debate to a U.S. national security concern."
Congress In October 2003 and again in June 2005, the McCain-Lieberman Climate Stewardship Act failed a vote in the US Senate. In the 2005 vote, Republicans opposed the Bill 49–6, while Democrats supported it 37–10.
In January 2007, Democratic House Speaker Nancy Pelosi announced she would form a United States Congress subcommittee to examine global warming. Sen. Joe Lieberman said, "I'm hot to get something done. It's hard not to conclude that the politics of global warming has changed and a new consensus for action is emerging and it is a bipartisan consensus.""Senators sound alarm on climate", The Washington Times, January 31, 2007 Senators Bernie Sanders (I-VT) and Barbara Boxer (D-CA) introduced the Global Warming Pollution Reduction Act on January 15, 2007. The measure would provide funding for R&D on geologic sequestration of carbon dioxide (CO2), set emissions standards for new vehicles and a renewable fuels requirement for gasoline beginning in 2016, establish energy efficiency and renewable portfolio standards beginning in 2008 and low-carbon electric generation standards beginning in 2016 for electric utilities, and require periodic evaluations by the National Academy of Sciences to determine whether emissions targets are adequate. However, the bill died in committee. Two more bills, the Climate Protection Act and the Sustainable Energy Act, proposed February 14, 2013, also failed to pass committee.
The House of Representatives approved the American Clean Energy and Security Act (ACES) on June 26, 2009, by a vote of 219–212, but the bill failed to pass the Senate.Greg G. Hitt; Stephan Power, "House Passes Climate Bill", June 27, 2009; The Wall Street Journal
In March 2011, the Republicans submitted a bill to the U.S. Congress that would prohibit the Environmental Protection Agency (EPA) from regulating greenhouse gasses as pollutants.Timothy Gardner, "Republicans launch bill to axe EPA carbon rules", Reuters March 3, 2011 As of 2012, the EPA was still overseeing regulation under the Clean Air Act.Court Backs E.P.A. Over Emissions Limits Intended to Reduce Global Warming June 26, 2012
In 2019, there were 130 elected congresspeople who had expressed doubt about the science of climate change.
Clinton administration Upon the start of his presidency in 1993, Bill Clinton committed the United States to lowering their greenhouse gas emissions to 1990 levels by 2000 through his biodiversity treaty, reflecting his attempt to return the United States to the global platform of climate policy. Clinton's British Thermal Unit (BTU) Tax and Climate Change Action Plan were also announced within the first year of his presidency, calling for a tax on energy heat content and plans for energy efficiency and joint implementations, respectively.
The Climate Change Action Plan was announced on October 19, 1993. This plan aimed to reduce greenhouse gas emissions to 1990 levels by 2000. Clinton described this goal as "ambitious but achievable," and called for 44 action steps to achieve this goal. Among these steps were voluntary participation by industry, especially those in the commercial and energy supply fields. Clinton allotted $1.9 billion to fund this plan from the federal budget and called for an additional $60 billion funding to come voluntarily businesses and industries.
The British Thermal Tax proposed by Clinton in early 1993 called for a tax on producers of gasoline, oil, and other fuels based on fuel content in accordance to the British Thermal Unit (BTU). The British Thermal Unit is a measure of heat corresponding to the quantity of heat needed to raise the temperature of water by one degree Fahrenheit. The tax also applied to electricity produced by hydro and nuclear power, but exempted renewable energy sources such as geothermal, solar, and wind. The Clinton Administration planned to collect up to $22.3 billion in revenue from the tax by 1997. The tax was opposed by the energy-intensive industry, who feared that the price increase caused by the tax would make U.S. products undesirable on an international level, and thus was never fully implemented.
In 1994, the U.S. called for a new limit on greenhouse gas emissions post-2000 in at the August 1994 INC-10. They also called for a focus on joint implementation, and for new developing countries to limit their emissions. Environmental groups, including the Climate Action Network (CAN), critiqued these efforts, questioning U.S. focus on limiting the emissions of other countries when it had not established its own.
The U.S. government under Clinton succeeded in pushing its agenda for joint implementation in the 1995 Conference of the Parties (COP-1). This victory is noted in the Berlin Mandate of April 1995, which called for developed countries to lead the implementation of national mitigation policies.
Clinton signed the Kyoto Protocol on behalf of the United States in 1997, pledging the country to a non-binding 7% reduction of greenhouse gas emissions. He claimed that the agreement was "environmentally strong and economically sound," and expressed a desire for greater involvement in the treaty by developing nations.
In his second term, Clinton announced his FY00 proposal, which allotted funding for a new set of environmental policies. Under this proposal, the President announced a new Clean Air Partnership Fund, new tax incentives and investments, and funding for environmental research of both natural and man-made changes to the climate.
The Clean Air Partnership Fund was proposed to finance state and local government efforts for greenhouse gas emission reductions in cooperation with EPA. Under this fund, $200 million was allotted to promote and finance innovation projects meant to reduce air pollution. It also supported the creation of partnerships between the local and federal governments, and private sector.
The Climate Change Technology Initiative provided $4 billion in tax incentives over a five-year period. The tax credits applied to energy efficient homes and building equipment, implementation of solar energy systems, electric and hybrid vehicles, clean energy, and the power industry. The Climate Change Technology Initiative also provided funding for additional research and development on clean technology, especially in the building, electricity, industry, and transportation sectors.
G.W. Bush administration
In March 2001, the George W. Bush Administration announced that it would not implement the Kyoto Protocol, an international treaty signed in 1997 in Kyoto, Japan that would require nations to reduce their greenhouse gas emissions, claiming that ratifying the treaty would create economic setbacks in the U.S. and does not put enough pressure to limit emissions from developing nations.Alex Kirby, US blow to Kyoto hopes, 2001-03-28, BBC News. In February 2002, President Bush announced his alternative to the Kyoto Protocol, by bringing forth a plan to reduce the intensity of greenhouse gasses by 18 percent over 10 years. The intensity of greenhouse gasses specifically is the ratio of greenhouse gas emissions and economic output, meaning that under this plan, emissions would still continue to grow, but at a slower pace. Bush stated that this plan would prevent the release of 500 million metric tons of greenhouse gases, which is about the equivalent of 70 million cars from the road. This target would achieve this goal by providing tax credits to businesses that use renewable energy sources.Bush unveils voluntary plan to reduce global warming , CNN.com, 2002-02-14.