A recent opinion article in The New York Times describes how we can expect the United States to rely more on treaty-like agreements than on actual treaties in the future. In such agreements, the U.S. agrees to try wholeheartedly to pass legislation that achieves the goals of the agreement, rather than signing a treaty and sending it to the Senate for ratification, because treaty ratification requires 67 votes in the Senate and legislation only requires 60 votes (with the modern-day filibuster).
Variations of this have been done in the past, even with what seem to be major multilateral treaties. For Instance, the 1947 General Agreement on Tariffs and Trade (GATT) was signed by the U.S., but never ratified by the Senate, though it is generally accepted as binding on the U.S.
The main source people cite to for recent treaties to which the U.S. is a party is TIAS, the Treaties and Other International Acts Series. However, TIAS only publishes treaties that have been ratified by the Senate (the same is true for the older United States Treaties and Other International Agreements (UST) and Treaties in Force).
So, if you are looking for an official citation to a treaty that the U.S. signed, make sure that the U.S. actually ratified the treaty before tearing your hair out. The treaty may not have been ratified, even if the U.S. has been following the treaty as though it was. For non-ratified treaties, find a citation in a non-U.S. source, like the United Nations Treaty Series (Hein link).
Note: An increasingly popular type of non-treaty agreement for the U.S. is the Executive Agreement, which requires no Senate approval. But Executive Agreements should not be as confusing as major multilateral treaties that the U.S. appears to follow, but were never ratified.
Ernster, the Virtual Library Cat
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