Pet peeve: Not enough pedantry with language use in publications.
Nation and country are not interchangeable. Words have meaning. Good journalist choose their words deliberately and have a deeper understand of language than the average person.
Sure, words certainly have meaning, but that meaning is constantly evolving and even differs from person to person.
For the common person and the common definition and use of the two words, they are very much interchangeable. The common person might not even notice the change in words because the generally used definitions of both are common enough.
Nation and country are not interchangeable. Words have meaning. Good journalist choose their words deliberately and have a deeper understand of language than the average person.