One legacy of President Trump’s “America First” foreign policy is the clear message to the rest of the world that no deal with the United States can be relied on once the president who made it is gone.

Trump spent his four years in office ripping up agreements made by several of his predecessors, most notability the 2015 Iran nuclear deal, which he called the “worst deal ever,” negotiated by President Barack Obama and signed by six other world powers, including U.S. allies Germany, France, the United Kingdom, and the European Union.