The only way that the United States of America can be compelled to military action is by treaty; no other instrument obligates us to defend another nation. It is a good thing that Ukraine was not admitted to NATO, which would have committed us to its defense by extension of the North Atlantic Treaty. It is astounding to observe so many people anxious to rush into war over a conflict that is none of our business and also beyond our present reach. Past empires were destroyed by such late-stage adventurism.
My best understanding is the term “treaty” is used in a more restricted legal sense in the U.S. than international law. These distinctions of procedure and terminology are not to affect the binding status of accords under international law. So, actually the Budapest is binding in international law.
“The ‘Budapest Memorandum’ follows the Helsinki Final Act repeating the provisions. Also, there many sources of international law that mandate Russia to respect Ukraine’s territorial integrity, i.e. provisions of the CSCE treaty and the UN Charter.
There are 3 forms under U.S. law:
1. congressional-executive agreements process: majority both Houses
2. sole-executive agreements process: President alone
3. traditional treaty process requiring Senate consent by a two-thirds vote
Also, there is a difference between self-executing treaties, which do not require additional legislative action, and non-self-executing treaties which do require the enactment of new laws!!!
But, all three classes are considered treaties under international law.
The President has also made international “agreements” through congressional-executive agreements (CEAs) that are ratified with only a majority from both houses of Congress, or sole-executive agreements made by the President alone. The congressional-executive and sole-executive agreements have been common throughout U.S. history and considered valid by Supreme Court.
http://papers.ssrn.com/sol3/papers.cfm?abstract_id=708243
ANYWAY: It is so unfortunate that the Ukraine basically made it self so very vulnerable by accommodating and trusting the other nations that entered the Budapest agreement