I've seen this used for both
- United States statehood (i.e. Puerto Rico)
- General statehood (i.e. ISIS)
I'm thinking that statehood is being confused with sovereignty in usage #2. Should we make it only about US statehood?
I'm not sure that it is important to precisely define every tag that potentially has dual meanings.
This is particularly true in a case like this one where the overlap flows from different aspects of a common concept. U.S. states are called "states" at all, because they were conceived as having some of the aspects of sovereignty even though it isn't as complete in the U.S. federal scheme as it is in the international sense.
The tag still distinguishes a post from the 99% of posts where none of the dual meanings are relevant, which is a great help in locating and organizing posts.
Also, most people putting in tags on their own posts aren't carefully reviewing the definitions anyway. They are merely looking at the choices and seeing which ones fit their intuitive ideas best.