On some level I do wonder just how bad things 'got' that the Federation would sell out it's morals to a group so obviously bad as the Son'a.
From Insurrection,
Picard: "In view of our losses to the Borg and the Dominion, the Council feels we need all the allies we can get these days."
During the second world war American allied herself with the Soviet Union, we subsequently found out that they were
much worse than the Nazis. In term of the amount of harm that they could do, the Sona were no-where near as bad as the Dominion, or even the Cardassians. And it's possible that additional information on the Sona was discovered after the partnership between the Federation and the Sona was already established.
The irony was that the Son'a were in bed with the Dominion at the same time.
From Insurrection,
Riker: "The Son'a are known to have produced vast quantities of the narcotic ketracel-white."
When Riker said that the Sona were producing the narcotic ketracel-white, what I got from Riker's use of the term "narcotic" is he meant that the Sona were not providing it to the Dominion, but were selling it interstellar as a street drug. If Ketracel-white were to have a similar effect upon the majority of Humanoids as it does on the Jem'hadar (including addiction) it would be like crack. Energy, strength, endurance, no sleep, added plus a maniac willingness to kill.
Ketracel-white can not be replicated, and might be the latest trendy "recreational" drug in the Alpha Quadrant.
Other than the mention of the white, no connection between the Sona and the Dominion was brought up.
But it'd be interesting to see some the ramifications of that war. Were there Federation member worlds for example who actually seceded from the Federation?
It would have been interesting subject to have explored, better handled in DS9 episodes though.
I just don't buy it as believable that they'd fall in with the Son'a, given that the Son'a are drawn in the movie as being such genuinely nasty guys (and unashamedly so).
The Sona conquered two species, and that was a half century before. The Federation has an mutual defense treaty with the Klingon Empire, who also engage in conquest.
The Sona took the two conquered species and made them into a labor class within the Sona society. One of the Federation's members (the Ardanans) also had a labor class on their world.
If you think about it, what is unusual in the least about the Federation doing business with the Sona?
