As an ENT fan that got to me too. I am in mourning for Andor.
Deranged Nasat opinions match my own, so I don't need to repeat that.
But one thing that does mark Andor out is that they've never had any successsful mixed Andorian/non-Andorian offspring. Unlike Vulcans and Humans who have had both had a significant upload of alien genetics into their societies and gene pools. Lt. T'Ryssa Chen is but merely one example. That seems to be the key difference here. Earth, Alpha Centauri and Vulcan have all become very open societies on a family level (no evidence for Tellar). Lots of alien in-laws. The Federation isn't just politics, it's family. On Andor however the Federation is just politics and it appeared to threaten family. Exit Federation.
By the way, was it implied in this novel that Chen was born on Vulcan? I seem to remember that.
Anyway, I don't think that the Federation is going to give up on Andor. They have far more invested in Andor than the Pact does.
I also wonder if the woes of Andor and Deneva can/will be solved by the terraforming tech revealed in Seize the Fire. No society was credited for originating that tech which to me was a glaring omission.
Deranged Nasat opinions match my own, so I don't need to repeat that.
But one thing that does mark Andor out is that they've never had any successsful mixed Andorian/non-Andorian offspring. Unlike Vulcans and Humans who have had both had a significant upload of alien genetics into their societies and gene pools. Lt. T'Ryssa Chen is but merely one example. That seems to be the key difference here. Earth, Alpha Centauri and Vulcan have all become very open societies on a family level (no evidence for Tellar). Lots of alien in-laws. The Federation isn't just politics, it's family. On Andor however the Federation is just politics and it appeared to threaten family. Exit Federation.
By the way, was it implied in this novel that Chen was born on Vulcan? I seem to remember that.
Anyway, I don't think that the Federation is going to give up on Andor. They have far more invested in Andor than the Pact does.
I also wonder if the woes of Andor and Deneva can/will be solved by the terraforming tech revealed in Seize the Fire. No society was credited for originating that tech which to me was a glaring omission.
It also reminds me of a line in "The Tears of Eridanus" from "Shattered Light", where an Andorian points out "a warrior culture has few sympathies" but that one of the strongest sympathies they do have is for family. As you say, on Andor family and the Federation ended up opposing one another (or so many Andorians came to believe), while it's easier for the other worlds to merge the two. Like Sonek Pran in "A Singular Destiny", who even explicitly says that the Federation is why he exists. 
Dayton Ward said you gave the text a Beta read, Therin. You knew about this!
