

State is defined as both:
A: A politically organized body of people usually occupying a definite territory especially one that is sovereign. (A country)
B: One of the constituent units of a nation having a federal government.
Many countries are made up of states because those states used to be independent states (countries) with the United States being the most obvious example. But this does not mean the other definition does not hold.
Thats not really a question i, or anyone, can answer on behalf of the english speaking world.
Its pretty common to refer to countries in organizations as “member states”. From the UN, to the CIS, to the African Union and EU, UNESCO, NATO, etc.
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