nation doesn't always mean state. there is a slippery slope between the concepts, but they are not always the same thing.
in today's parlance, consider those who are fighting for black liberation. it is possible to see that fight as a defensive one against people who target black people specifically. it is also possible to see it as an offensive one to get more power for a particular group. (both are true to varying degrees, of course.)
[i haven't read much bakunin either but have certainly read about him that he said contradictory things, and was speaking to different audiences at different times and would use different words to try to be clear.]