What I'm saying is this: if one abandons the principles for which one is fighting, what is the point of fighting for them? War is hell (part of why it should be avoided at all costs and used only as a last resort).
If your moral principles are such that you break them by defending yourself (or defending yourself half-way effectively), then your moral principles are fundamentally suicidal in this universe and any group following them will disappear from the universe shortly, outcompeted - enslaved/exterminated/etc - by others.
Indeed, the only way such a group can survive for any period of time is if another group (with more down-to-earth principles) protects the first one.
I have also not forgotten about Section 31 and don't condone their actions or existence to begin with.
Without S31's actions, Odo's attempt at the end would have amounted to nothing.
By praising Odo's actions as 'the way to do it' you indirectly praise S31's actions as 'the way to do it'. Denying this - or claiming the contrary - doesn't change it.
Well the show manufactures the circumstances the characters react to. The could make either choice the "correct" choice. For instance in the episode The First Duty, Wesley ultimately chooses to tell the truth because it is the right choice. The writers said they had an alternate scenario in mind where the correct choice would be to lie because it protects the team.
Therefore in the show the writers chose to make the correct choice the more morally ambiguous ones in order to show the horrors of war. It doesn't seem to be unreasonable to think that the writers could have made the correct choice the morally "righteous" choice more often. It may not have as much dramatic impact on the viewer, but it would be more faithful to the world the characters live in as established by that world's creator.
TNG couldn't negotiate with the Borg thats true, but they couldn't negotiate with a storm either. That was the point. They were a unique entity without reason.
Star Trek doesn't have to present a war as it would occur in the real world, because star trek is not the real world.
So, you essentially want children's tales, to tell you cushy facts that blatantly contradict reality, just because reality is too inconvenient for your ivory tower, cushy philosophying?
BTW that was the greatest weakness for TNG. Annoying, when it was obvious that, from a real world perspective, the 'correct' choice was noting of the sort; in most other circumstances where it occured, it merely diluted the show with simplistic/unrealistic black/white with nothing in between - it was just like watching a cartoon for 6 years old.