February 23, 2026
Can a President Unilaterally Withdraw—and Rejoin—the UN Climate Treaty?
This article was originally published in Lawfare.
On Jan. 7, the Trump administration withdrew the United States from more than 60 international agreements and organizations, including the United Nations Framework Convention on Climate Change (UNFCCC). The administration justified these withdrawals by deeming the agreements “contrary to the interests of the United States” and characterized them as “anti-American, useless, and wasteful.” When the Trump administration announced the United States’s withdrawal from the UNFCCC, it revived two long-standing but unresolved constitutional questions: (a) Can a president unilaterally terminate a Senate-ratified treaty—and if so, (b) can a future president unilaterally rejoin it?
This executive dominance over treaty commitments—allowing presidents to withdraw and rejoin major international agreements at will—creates profound instability in U.S. foreign relations.
Trump’s withdrawal from these organizations marks a significant setback for international climate progress. The United States is the world’s largest historic emitter of greenhouse gases, and its exit from the UNFCCC and other climate agreements ends U.S. participation in the annual Conference of the Parties, cedes international climate leadership to China and the EU, and eliminates any U.S. influence over prospective climate rules, transparency frameworks, and adaptation finance. The U.S. withdrawal announcement has already prompted sharp criticism. The Union of Concerned Scientists, for example, released a statement calling the decision “a new low” for the Trump administration, while former Environmental Protection Agency (EPA) Administrator Gina McCarthy characterized the decision as “shortsighted, embarrassing, and foolish.” Furthermore, the U.S.’s decision to repeal the “endangerment finding” under the Clean Air Act marks another setback for climate progress. Without U.S. economic and political influence in negotiations and climate efforts on both the international and domestic fronts, the rest of the world will likely struggle to achieve meaningful climate goals.
Read the full article in Lawfare.
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