This bill would amend a 1954 law to establish that if all NATO member countries unanimously approve Ukraine's membership process, the United States would have legal grounds to immediately withdraw from the North Atlantic Treaty, the alliance that has bound the U.S. and European nations together since 1945. The legislation was introduced in July 2024 by Senators Mike Lee and Tommy Tuberville. The bill does not require the U.S. to withdraw if Ukraine joins NATO—it merely provides a legal basis for withdrawal if that occurs. There is no specific funding or timeline mentioned in the bill. This legislation would essentially allow the U.S. to use Ukraine's NATO membership as a trigger to exit the alliance, though the decision to actually withdraw would remain with Congress and the President.