Introduction

The climate and energy policy of the United States during the Trump administrations represents a marked departure from the trajectories established by previous federal administrations, characterized by a pronounced emphasis on regulatory rollback, expansion of fossil fuel production, and the pursuit of energy independence, alongside a reduction in federal investment in climate science and renewable energy initiatives. These policy decisions significantly reshaped domestic governance, the structure and dynamics of the energy sector, and the United States’ positioning in international climate negotiations. This study provides a comprehensive assessment of the Trump administration’s climate and energy policies, with particular attention to regulatory rollbacks, withdrawal from the Paris Agreement, promotion of fossil fuels, and the administration’s conservative approach to energy governance, which prioritized short-term economic growth, employment in traditional energy sectors, and national energy security over federally mandated emissions reductions and the acceleration of renewable energy deployment.

Regulatory Rollbacks and Deregulation

A defining characteristic of the Trump administrations’ approach to climate and energy policy was the systematic dismantling of regulatory frameworks designed to reduce greenhouse gas emissions and ensure environmental protection, reflecting a conservative ideological commitment to minimizing federal intervention in energy markets while maximizing domestic economic growth. Central among these policy actions was the repeal of the Clean Power Plan, which had established enforceable emissions reduction targets for coal-fired power plants, projected to reduce U.S. carbon dioxide emissions by approximately 32% below 2005 levels by 2030, thereby creating a legal and regulatory pathway for increased reliance on fossil fuels during the administration. The repeal of this plan was accompanied by a broader deregulatory agenda, including the relaxation of vehicle fuel economy standards under the Corporate Average Fuel Economy (CAFE) program, which previously mandated roughly 5% annual efficiency improvements through 2025, and the easing of methane emission restrictions from oil and gas operations, which allowed higher levels of methane, a gas approximately 84 times more potent than carbon dioxide over a 20-year horizon, to escape into the atmosphere. These measures were defended as necessary to reduce regulatory burdens on industry, stimulate employment in coal, oil, and natural gas sectors, and lower domestic energy prices; however, they carried significant environmental and public health trade-offs, including increased particulate matter and nitrogen oxide concentrations that negatively impacted air quality and human health.

Legal and institutional constraints played a critical role in shaping the implementation and ultimate effects of these deregulations, as multiple court decisions, particularly at the appellate level, intervened to challenge the rollback of key policies, and state-level governments, notably California, New York, and Washington, adopted autonomous climate initiatives to partially offset federal disengagement. These state-led initiatives included robust cap-and-trade systems, renewable portfolio standards, and mandates for zero-emission vehicles, highlighting the complexity of multi-level governance in the United States and the limitations of unilateral executive action in reversing climate policy trends. Despite these constraints, the Trump administration’s deregulatory actions produced a tangible shift in the emissions trajectory of the United States, effectively slowing the pace of decarbonization in key sectors while reinforcing the administration’s conservative narrative that prioritized economic growth and market-driven solutions over federally imposed environmental constraints.

Withdrawal from the Paris Agreement

In June 2017, President Trump announced the formal intention of the United States to withdraw from the Paris Agreement, a landmark international accord that sought to limit global temperature rise to well below 2°C above pre-industrial levels, with aspirational goals of limiting warming to 1.5°C, and which had committed the United States to reducing greenhouse gas emissions by 26-28% below 2005 levels by 2025. The withdrawal was justified by the administration on the basis of protecting American economic interests, preserving sovereignty in domestic regulatory decision-making, and avoiding what was characterized as burdensome international obligations that could disadvantage U.S. industry. The consequences of this decision were both symbolic and substantive: the United States’ retreat signaled a diminution of its leadership role in international climate governance, weakened collaborative frameworks for technology transfer and climate finance, and introduced uncertainties into global emissions monitoring and compliance mechanisms.

Despite federal disengagement, subnational actors, including more than twenty-five states and hundreds of municipalities and private-sector entities, pledged to uphold Paris-aligned emissions reductions, creating a decentralized and fragmented approach to climate governance within the United States. While these decentralized efforts partially mitigated the impact of federal withdrawal, they lacked the comprehensive scale and coordination necessary to achieve the aggregate emissions reductions originally envisioned under the Paris commitments. Internationally, U.S. withdrawal provided a window for other nations, particularly European Union member states and China, to assert leadership in climate policy negotiations, invest in renewable energy technology deployment, and establish emissions reduction targets, thereby recalibrating the geopolitical balance of climate governance.

Figure 1. U.S. Greenhouse gas emissions and projections, MtCO2e

Source: REPEAT Project, US nationally determined contribution

Impacts on Greenhouse Gas Emissions and Energy Sectors

The regulatory and policy environment of the Trump administrations had measurable effects on greenhouse gas emissions in the United States. Data from the Environmental Protection Agency indicate that total U.S. emissions increased by approximately 5.7% between 2020 and 2022, largely as a consequence of economic recovery following the COVID-19 pandemic combined with the deregulatory measures enacted between 2017 and 2020. The electricity sector experienced an additional 100 million metric tons of carbon dioxide-equivalent emissions during this period, driven by continued reliance on coal and natural gas-fired generation, while the transportation sector, as the largest single contributor to national emissions, continued to increase due to relaxed fuel economy standards and insufficient federal incentives for electric vehicle adoption and infrastructure development.

Simultaneously, the renewable energy sector experienced slower growth than projected under previous federal trajectories. Solar energy installation growth, which had averaged 20-25% annually during the Obama administration, declined to roughly 10% annually under the Trump administrations, reflecting the combined effects of tariffs on imported photovoltaic panels, reductions in the Investment Tax Credit (ITC) and Production Tax Credit (PTC), and diminished federal support for large-scale utility solar and offshore wind projects. Wind energy deployment was similarly constrained, with significant delays in permitting and limited federal incentives, which, in combination with market competition from low-cost natural gas, slowed the transition toward a diversified and low-carbon energy portfolio.

Figure 2. U.S. Greenhouses Gas Emissions by Economic Sector

Source: U.S. EPA’s Inventory of U.S. Greenhouse Gas Emissions and Sinks

American Energy Policy Under the Trump Administrations

The Trump administrations’ energy policy was characterized by a conservative emphasis on domestic fossil fuel expansion, energy independence, and market-driven economic growth, with deregulation serving as a central instrument to achieve these objectives. The “Unleashing American Energy” initiative of 2017 exemplified this approach, prioritizing increased oil, natural gas, and coal production on federal lands, expedited permitting for pipelines and other energy infrastructure projects, and reduced federal oversight of extraction activities. During this period, U.S. crude oil production increased from approximately 8.9 million barrels per day in 2016 to 12.2 million barrels per day in 2019, establishing the United States as the world’s largest oil producer and a net exporter of petroleum products by 2020. Natural gas production similarly rose, reaching 34.7 trillion cubic feet in 2019, predominantly through shale gas extraction, while coal production experienced a temporary stabilization due to regulatory relief despite longer-term market pressures favoring natural gas and renewables.

While fossil fuel production expanded, the Trump administrations’ policies actively constrained federal incentives for renewable energy development. Tariffs on imported solar panels and wind turbine components, coupled with reductions in the ITC and PTC, slowed the deployment of utility-scale solar and wind projects, reducing projected annual renewable energy growth from approximately 25% under prior federal policies to 10-12% during the Trump administrations. These measures were justified on conservative grounds, emphasizing domestic job protection, the preservation of U.S. manufacturing competitiveness, and the avoidance of market distortions caused by foreign subsidies, yet they delayed progress toward decarbonization and reinforced the nation’s reliance on fossil fuels.

Energy policy under these administrations also had significant international dimensions. The expansion of fossil fuel exports was framed as a mechanism to enhance U.S. geopolitical leverage and global market competitiveness, while reduced participation in multilateral climate initiatives reflected a conservative orientation toward national sovereignty and economic prioritization over international climate obligations. Analyses projecting a potential second Trump term suggested that such policies would likely have continued, further emphasizing fossil fuel expansion, deregulation, and market liberalization while resisting binding international emissions commitments, thereby sustaining short-term economic and energy security benefits at the cost of higher domestic greenhouse gas emissions and slower renewable energy adoption.

Legal, Institutional, and Political Constraints

Despite the Trump administrations’ deregulatory agenda, legal, institutional, and political constraints imposed significant limits on policy implementation. Judicial oversight frequently intervened to delay or block repeals of major climate and energy regulations, including the Clean Power Plan, vehicle fuel efficiency standards, and methane emissions rules, highlighting the limitations of executive authority within the U.S. legal system. Moreover, state-level governments maintained robust climate programs, including cap-and-trade initiatives, renewable portfolio standards, and mandates for zero-emission vehicles, partially counterbalancing federal deregulatory actions. Political polarization and congressional gridlock further constrained the development of enduring legislative solutions, leaving administrative action as the primary mechanism for implementing the Trump administrations’ climate and energy agenda. In combination, these legal, institutional, and political factors underscored the complexity of U.S. climate governance and the inherent limitations of executive-driven policy in the context of multi-level federalism.

U.S. - EU Climate and Energy Policy Cooperation

Transatlantic cooperation between the United States and the European Union has historically represented one of the most influential bilateral mechanisms for shaping global climate and energy governance, combining regulatory leadership, technological innovation, and diplomatic influence to advance both mitigation and energy transition objectives. The EU has pursued ambitious climate targets over the past two decades, committing to a 55% reduction in greenhouse gas emissions by 2030 relative to 1990 levels, achieving approximately 38% of electricity generation from renewable sources by 2020, and setting legally binding frameworks for carbon pricing and emissions trading through its European Union Emissions Trading System (EU ETS), which covers roughly 45% of the EU’s greenhouse gas emissions. In parallel, the United States, under federal and subnational frameworks, pledged under the Paris Agreement to reduce emissions by 26-28% below 2005 levels by 2025, although implementation varied depending on administration priorities, state-level initiatives, and market forces. Transatlantic cooperation has included joint research and development programs in clean energy technologies, such as offshore wind, solar photovoltaics, energy storage, and smart grid infrastructure, which are critical for modernizing energy systems and decarbonizing electricity generation in both regions.

Even in periods of partial policy divergence, such as the Trump administrations’ withdrawal from the Paris Agreement and prioritization of fossil fuel expansion, cooperative mechanisms persisted through subnational actors, private-sector engagement, and multilateral forums. U.S. states including California, New York, and Massachusetts continued to align emissions reduction strategies with EU regulatory frameworks, participate in transatlantic clean energy initiatives, and develop subnational carbon pricing programs that mirrored European approaches. Corporate actors, particularly in the technology, energy, and financial sectors, maintained partnerships across the Atlantic to develop and deploy renewable energy projects, green infrastructure, and low-carbon supply chains, demonstrating the resilience of bilateral collaboration even in the absence of full federal alignment. Quantitatively, U.S. investments in transatlantic energy R&D, including joint projects in offshore wind and battery storage, reached approximately $1.2 billion between 2017 and 2020, reflecting both economic and strategic incentives for collaboration, while EU imports of U.S. liquefied natural gas (LNG) increased by over 80% during the same period, illustrating the intersection of energy security, trade, and climate policy.

Policy coordination has extended beyond technological collaboration to include harmonization of regulatory standards, particularly in energy efficiency, emissions measurement, and carbon market mechanisms. The EU ETS provides a model for subnational U.S. programs, such as California’s cap-and-trade system, which covers approximately 85% of the state’s emissions and has facilitated the linking of regional carbon markets with European frameworks in terms of reporting standards, crediting, and verification methodologies. These regulatory alignments enhance market predictability, reduce transaction costs for multinational companies, and provide stronger signals for investment in low-carbon technologies. Moreover, collaborative engagement in international climate negotiations, including UNFCCC forums, has allowed the U.S. and EU to coordinate positions on technology transfer, climate finance, and mitigation commitments for developing countries, demonstrating the strategic importance of transatlantic cooperation in advancing global climate objectives.

Economic considerations have reinforced the durability of U.S. - EU collaboration. Renewable energy deployment in the EU has created a market for U.S.-based clean energy technology exports, including advanced turbines, solar panels, and smart grid components, while U.S. participation in European-led green finance initiatives, such as the European Investment Bank’s climate projects, has facilitated transnational capital flows into sustainable infrastructure. In addition, collaborative research through initiatives such as the U.S. - EU Clean Energy Technology Network has supported knowledge sharing, workforce development, and deployment of emerging technologies, enabling both regions to accelerate the transition toward decarbonized energy systems. By 2020, joint U.S. - EU efforts had contributed to over 2 GW of transatlantic offshore wind capacity, with projects under development expected to exceed 10 GW by 2030, illustrating the tangible impact of coordinated policies and investment strategies.

Strategically, U.S. - EU climate and energy cooperation has provided a platform to align energy security, economic competitiveness, and environmental objectives. While the Trump administrations emphasized fossil fuel expansion and regulatory independence, the EU’s consistent climate and energy targets created a framework for dialogue, negotiation, and subnational engagement, preventing complete decoupling of U.S. and European climate strategies. This cooperative dynamic also reinforced market confidence in low-carbon technologies, provided standards for measurement and verification, and encouraged multinational corporations to adopt decarbonization pathways compatible with both U.S. and European policies. Looking forward, U.S. - EU cooperation is poised to play a critical role in global climate governance, including the scaling of clean energy infrastructure, harmonization of emissions reporting standards, and joint support for innovation in carbon capture, hydrogen technologies, and energy storage, ensuring that transatlantic policy alignment continues to influence both regional and global energy transitions despite fluctuating federal priorities.

Challenges and Limitations

The Trump administrations’ climate and energy policies faced numerous challenges, including legal opposition, market dynamics, state-level countermeasures, and international pressure. Employment gains in fossil fuel sectors were modest relative to environmental and public health costs, while emissions reductions were stalled or reversed in key sectors. Multi-level governance complexity, encompassing interactions between federal, state, and local authorities, further constrained policy implementation and effectiveness, illustrating the structural limitations of executive-driven climate and energy governance in the United States. Additionally, the administration’s retreat from international climate engagement diminished U.S. influence in shaping global emissions reduction pathways, creating a policy environment characterized by both domestic and international challenges to achieving long-term decarbonization objectives.

Prospects for Future Policy and Governance

The Biden administration’s reentry into the Paris Agreement, coupled with renewed federal climate initiatives, represents a partial reversal of Trump-era deregulation and a renewed commitment to decarbonization. Technological advances in renewable energy generation, energy storage, carbon capture and storage, and grid modernization provide potential pathways for achieving emissions reductions, contingent upon consistent regulatory frameworks and sustained policy support. State governments, corporations, and private investors will continue to play an essential role in realizing these objectives, reflecting a multi-level governance model that balances federal priorities with decentralized innovation.

Geopolitical considerations, including U.S. - China climate relations, European Union energy and climate strategies, and the integration of carbon markets, will influence domestic policy, offering both opportunities and constraints for emissions reduction. Conservative energy strategies in future administrations may adopt hybrid approaches that integrate market-driven renewable energy adoption with continued fossil fuel competitiveness, balancing economic growth, energy security, and environmental protection.

Conclusion

The climate and energy policy of the Trump administrations represented a conservative reorientation emphasizing deregulation, fossil fuel expansion, and energy independence, while reducing federal support for renewable energy and international climate commitments. These policies yielded measurable short-term economic and strategic gains, including increased fossil fuel production, expanded exports, and stabilized employment in traditional energy sectors, but they also produced higher greenhouse gas emissions, slowed renewable energy deployment, and diminished U.S. credibility in global climate governance. Judicial oversight, state-level initiatives, and market dynamics partially mitigated these effects, highlighting the constraints of executive-driven policy. Future climate and energy governance in the United States will require coordinated federal leadership, state-level innovation, technological advancement, and international cooperation to reconcile economic growth, energy security, and environmental stewardship. The experience of the Trump administrations underscores the importance of durable, science-based, and legally robust policy frameworks capable of withstanding political transitions and supporting long-term decarbonization objectives.

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