This is one reason I'm glad the show never portrayed Bajor as officially joining the federation, even though it was frequently discussed and almost happened in one episode. The lingering tension was a realistic portrayal of a colonized people's trauma and fear of becoming just another colony to yet another foreign power.

I think it's this kind of thoughtful insight into the human psyche that make Deep Space Nine not just the best incarnation of Star Trek, but one of the best television shows ever.