The Second Trump Administration and the System of International Multilateral Institutions

Abstract

Since his presidential inauguration in 2025, Donald Trump has been reshaping the 21st century system of multilateral institutions – or at least the American role in it – with extraordinary speed and scale. Even though such measures were partly present in his previous presidential term, and displayed in the 2024 presidential campaign, the rapid, decisive, and inexorable retreat – without any apparent consideration of the effects – from the organizations traditionally created by the United States, in which the U.S. even played a dominant and sometimes leading role for decades, has caused remarkable outcry. In parallel, the administration also transformed U.S. (national) institutions, allegedly pursuing governmental – fiscal – efficiency This study reviews the background, nature, and consequences of the decisions of the second Trump administration for respective institutions and international treaties, taking stock of the first year of the presidency.