A Roller Coaster: 25 Years of U.S. Climate Policy

From Bush to Trump: 25 Years of U.S. Climate Policy Roller Coaster examines the shifting approaches to climate policy during the presidencies of George Bush, Barack Obama, Donald Trump, Joe Biden, and in Trump’s second term. Building on a qualitative case comparison, Unger and Thielges analyse the (climate) domestic and foreign policies of the US presidents and interpret their impacts on the European Union. Their analysis shows that climate policies and policy ambitions have varied greatly between the different presidencies.

Bush (2001–2009) shocked European partners when he withdrew the USA from the Kyoto Protocol. For a long time, the Bush Administration refused to acknowledge the challenges posed by human-induced climate change. Later, with the creation of the Global Climate Initiative and the Asia Pacific Partnership on Clean Development and Climate, Bush instead sought to establish a voluntary initiative that would operate in competition with the United Nations Framework Convention on Climate Change (UNFCCC). On the domestic front, Bush gave climate policy low priority, although he did champion low-carbon technologies such as hydrogen.

In contrast, Obama (2009–2017) positioned climate policy and green technologies as drivers of economic growth, job creation, and improved healthcare. Obama brought the United States into the Paris Agreement and established international partnerships to promote renewable and ‘clean’ energies. For the first time in US history, Obama set national emissions targets, regulated greenhouse gas emissions in the electricity sector with the Clean Power Plan and boosted government investment in low-carbon technologies. Under Obama, the Environmental Protection Agency (EPA) and other agencies became important players in climate policy.

In his first term (2017–2021), Trump initiated the United States’ withdrawal from the Paris Agreement and from international cooperation on climate policy. His administration’s “energy dominance” policy was chiefly centred on fossil fuel production and deregulation, but (then) did not exclude renewables and, notably, kept up support for technologies such as carbon capture and storage (CCS). Trump rolled back numerous climate and environmental regulations and weakened the National Environmental Protection Agency (EPA).

Biden (2021–2025) led the USA back into the Paris Agreement and restored ties with many international partners on climate policy. His administration set ambitious national climate policy targets, including reducing greenhouse gas emissions to 50–52% below 2005 levels by 2030, a 50% share in zero-emission vehicle sales by 2030 and the decarbonization of the electricity sector by 2035. Under Biden, the first national climate legislation, the Inflation Reduction Act (IRA), was passed. This and other legislation led to substantial investment in low-carbon technologies.

The new Trump Administration (from 2024) denies human-induced climate change and has taken drastic action to dismantle US policies on climate change and renewable energies. Trump has withdrawn the US from the Paris Agreement for a second time. In addition, he has terminated numerous climate and energy partnerships and halted all international funding for climate action and development cooperation. His administration has suspended countless national climate targets and regulations, including regulations to curb methane emissions. Trump has also halted federal investment in renewable energies such as wind power; instead, looking to boost the roles of coal, oil and gas. He has weakened relevant federal agencies, dismissed thousands of employees and has sought to defund climate science.

US climate policy and transatlantic relations

The analysis by Unger and Thielges finds that the US cannot be considered a reliable and stable climate policy ally for the EU during the past 25 years. Under Democratic presidents, the US and the EU typically found more common ground on broader (climate) objectives and created cooperation opportunities. However, even then, policy approaches differed significantly, for instance with regard to binding vs. non-binding climate targets, carbon pricing, or positions within the framework of the UNFCCC negotiations. Relations are characterised by a back and forth between political tensions and cooperation. Even under Democratic presidents, fossil fuel production soared in the USA. And, finally, there was always the looming risk that the next US president would reverse his predecessor’s course of action. Climate cooperation with Republican presidents was often difficult or not possible at all for the EU. 

The EU has responded to the changing US climate policies with different strategies. On the one hand, it has tried to persuade the USA to return to multilateral agreements. On the other hand, it has strengthened its own climate protection targets and sought to assume a leading role internationally in climate protection. Domestically,  the EU is working on reducing its dependence from fossil fuel imports with policies such as the European Green Deal 

Trump's second term in office is, nevertheless, a departure from previous patterns. It signals a more extreme divide and potential for transatlantic conflict. A rift between these two important players does not bode well for global climate policy. While Trump’s policy will set the US back years in terms of emissions reductions, the EU will struggle to fill both the financial and the power gap that the US leaves in the international climate regime.
 

Publication:
Unger, C., Thielges, S. From Bush to Trump: 25 Years of U.S. Climate Policy Roller Coaster. Z Außen Sicherheitspolit (2025). https://doi.org/10.1007/s12399-025-01070-5