On his first day back in office, President Donald Trump signed an executive order beginning the formal withdrawal of the United States from the Paris Climate Agreement, a landmark pact between nations that aims to limit global warming to well below 2°C.
It marked the second time Trump had taken this step, having previously announced the U.S. withdrawal from the accord during his first term in 2017. This week’s move will make the U.S. one of only four countries in the world that are not party to the agreement, drawing criticism from environmental advocates and global leaders.
While the previous stretch where the U.S. was no longer part of the deal lasted only four months—the withdrawal was finalized in Nov. 2020 and President Joe Biden rejoined the Paris Agreement in early 2021—the impact was profound. The process not only disrupted international climate diplomacy but also damaged the U.S.’s credibility on the world stage, sending a signal of unpredictability and retreat from global leadership at a critical moment in the climate crisis. The move also halted essential contributions to climate finance, leaving developing nations without vital support for mitigation and adaptation efforts.
Yet this week’s withdrawal news was hardly a surprise: despite the outcry in his first term, Trump had long promised to exit the agreement if he returned to office, referring to it during his campaign for a second term as “unfair” and “one-sided.” The rhetoric echoed his previous justification for the pullout: that the agreement imposed unfair economic burdens on the U.S. while allowing other countries, like China, to continue polluting.
Now, as Trump reinitiates the process of withdrawing from the agreement, the immediate effects could mirror those of the previous exit. Some environmental advocates are concerned the move will once again undermine the country’s standing in global climate efforts, potentially emboldening other nations to scale back their own commitments. The Trump Administration “must stay focused on growing our clean energy industry,” says Gina McCarthy, who served as White House climate adviser under President Joe Biden. “The United States must continue to show leadership on the international stage if we want to have any say in how trillions of dollars in financial investments, policies, and decisions are made that will shape the course of our economy and the world’s ability to fight climate change.”
To get a better sense of what the impact might be this time around, here are some of the consequences of Trump’s previous withdrawal from the Paris Climate Agreement.
Damaged international climate diplomacy
When Trump announced the U.S. withdrawal from the climate agreement in 2017, the move reverberated around the globe. Nearly 200 nations had committed to reducing greenhouse gas emissions under the pact when it was created in 2015, and they had set ambitious targets to keep global temperature rise well below 2°C, and ideally below 1.5°C.
The retreat significantly weakened the U.S.’s position in international climate negotiations and sent a signal of instability to other countries.
In the absence of U.S. leadership, countries like China, India, and members of the European Union began to assert themselves more forcefully on climate-related issues. China, in particular, capitalized on the vacuum left by the U.S., positioning itself as a leader in the global green energy transition. Even though China is still the biggest source of the carbon pollution driving up global temperatures, the nation met its renewables targets in 2024, six years early, and has installed more solar and wind power than any other country.
The U.S.’s withdrawal also disrupted critical alliances with other nations committed to ambitious climate goals. Climate talks largely stalled under Trump’s first term, leading some nations to question the reliability of the U.S. as a partner in addressing the climate crisis.
Halted climate finance
One of the most significant consequences of the U.S. withdrawal from the Paris Agreement was the abrupt end to climate finance. The Obama Administration had committed to contributing to the Green Climate Fund (GCF), which helps developing countries mitigate and adapt to the impacts of climate change. With the U.S. out of the agreement, funding for this initiative was immediately cut, leaving nations primarily in the Global South without critical resources.
The fund had been designed to help developing countries transition to renewable energy, build resilient infrastructure, and adapt to the rapidly changing climate. The U.S. had pledged $3 billion to this fund, though under Trump, only a fraction of that commitment was honored. The lack of financial backing also slowed global progress on climate adaptation and emissions reduction, especially in poorer nations that are most vulnerable to the effects of climate change.
Countries that had already been relying on these funds, such as small island nations and nations in Africa, voiced frustration at the U.S.’s failure to uphold its promises, which had been key to the success of the Paris Agreement. “Keeping to 1.5 degrees is quite simply a matter of survival,” Ethiopia’s top climate official Debasu Bayleyegn Eyasu, who chaired the Climate Vulnerable Forum (CVF), a group of developing nations most threatened by climate change, said at the May 2017 climate talks in Germany. “For all of us, the Paris Agreement is our lifeline.” The CVF said in a statement at the time that the U.S.’s withdrawal from the Paris Agreement “signifies an endangerment of the more than one billion people our Forum represents in Africa, Asia, the Caribbean, Latin America and the Pacific.”
Environmental rollbacks
On the domestic front, the U.S. withdrawal from the Paris Agreement was accompanied by a series of deregulatory moves that undermined the country’s efforts to reduce emissions. The Trump Administration rolled back more than 100 environmental regulations, from fuel efficiency standards for cars to restrictions on power plant emissions.
Perhaps the most symbolic of these changes was the decision to ease restrictions on coal-fired power plants, a major source of greenhouse gas emissions in the U.S. Trump at the time argued that these actions were designed to revive the U.S. energy sector and boost job growth in coal-producing regions. However, many experts warned that these moves would make it harder for the U.S. to meet its emissions targets under the Paris Agreement, which had been set in alignment with the broader global goals to limit warming to well below 2°C.
Additionally, Trump’s withdrawal was seen as an open invitation for other nations to scale back their own climate commitments. While some countries, particularly in Europe, reaffirmed their commitments to the accord, the global momentum to cut emissions stalled in the face of U.S. retrenchment. According to the International Energy Agency, global energy-related CO2 emissions increased by 1.7% in 2018, the same year that the U.S. formally began the process of withdrawal, after three years of relatively steady declines.