United Nations Ambassador Nikki Haley announced, over the weekend, that the Trump Administration has decided to pull the U.S. out of a non-binding U.N. agreement calling for a global response to the international flow of migrants.

Ambassador Haley made the decision final on Monday.

In a statement released to media over the weekend, Ambassador Haley made it clear that the U.N.'s Global Compact on Migration, while technically non-binding and host to no enforcement clause that would negatively impact the United States if it failed to fulfill its commitment, violated the Trump Administration's priorities on immigration and put American borders at risk.

"[Our] decisions on immigration policies must always be made by Americans and Americans alone," the statement read. "We will decide how best to control our borders and who will be allowed to enter our country. The global approach in the New York Declaration is simply not compatible with U.S. sovereignty."

The Compact was, itself, fairly innocuous, at least on its face, calling for "enhance[d] international cooperation in dealing with present and future waves of immigration," a more global approach to border security, and a promise not to harass child migrants who may not qualify for refugee status. But in practice, the Trump Administration believes it could be used to shame the United States into loosening its immigration laws.

Sources told Foreign Policy that Ambassador Haley was in favor of remaining as a party to the treaty, but Secretary of State Rex Tillerson was not, and the Trump Administration eventually fell on Tillerson's side.

The U.N. responded by, well, sounding dejected.

"The role of the United States in this process is critical as it has historically and generously welcomed people from all across the globe and remains home to the largest number of international migrants in the world," a statement from the U.N.'s body on migration reads. "As such, it has the experience and expertise to help ensure that this process leads to a successful outcome."