The TEC had a millina of prospartity and peace. They must of been united for that to happen. Its only now that the Vasari and Advent come busting down the door are they fighting. Even then the TEC are united in their cause to survive. Heroic and Noble IMHO. I dont consiter the Advent human. They have progressed far beyond that with their experements and drugs.
I guess its all in how you look at it.
Well, the TEC brought the Advent down upon themselves. TEC literally went jihad on them (Ironic, seeing as to how the Advent now are). Reading the lore, it seems as if the TEC had quasi-religious objections to Advent practices. They then exiled them from their homeworld. If ranking the races on 'nobility of the cause', I'd rank Advent at the top, TEC second, forced relocations are not noble, and the Vasari third, being slavers and all.
EDIT - Why does this sub-forum not appear, for me anyway, in the main Sins forum tree?