The 1947 Inter-American Treaty of Reciprocal Assistance appears to be breaking as the US seeks to pull all of the Americas into a Venezuelan War (archived, archived). While the treaty was invoked several times through the Cold War and most recently after 9/11, the American country of Uruguay doesn't seem to see why they should support US military action against Venezuela. Especially if the US wasn't willing to support Argentine military action against Britain in 1982.
It appears that after the US failure in 1982 to love the Americas as much as Americans love Miami, the symbollic "9/11 bad, never forget" invocation was all the cooperation this relic of the fading world order had left.
It's actually hysterical to watch, the idiots did a whole soviet union collapse upon themselves, they've not even the excuse available "someone else did it".