With no change to their lifestyle, and no visible enemy to resist, most UEF citizens would not be inclined to resist.
Also, note that the UEF citizens are (on average) highly educated and open-minded. I am fairly certain the GTVA is betting on that for making them understand that now that the war is over, it's better for all humanity if they keep living peacefully. They may not completely enjoy it, but they will be sensible to rational argumentation if the Tevs play their cards right.
Also, educated masses are harder to make revolt than uneducated masses.
Actually that's false - you need an educated class to foster the revolution, plus there is also non-violent versus violent resistance. As I said, understanding does not breed acceptance - understanding can be used in civil resistance, think Thoreau.
BTW my arguments make it sound like I am more pro-UEF than I really am. I almost wrote these paragraphs below earlier and perhaps I should've done so.
I am pro-UEF in the game, but outside of the specific construction of the BP universe I would be very uncomfortable with their system of government. While we do not know the exact details of the local governments, I would assume they are some sort of democracy, however, still an organization like the Council of Elders would make me quite uncomfortable. That wouldn't justify an invasion of their home system without provocation since their people are not being repressed or degraded, but it's not something I'd try to emulate in real life.
Plus, while people on the board refer to GEFs as space hippies, truthfully Ubuntu is cloaked in that language as well: "Ubuntu flower girl". But the reality is that the Elders are more pragmatic than pacifist. Yes they attempted to broker peace with the GTA, but this is also an organization that allows and cooperates with an organization like the Fedayeen. It is an organization that built a pretty nice fleet despite their isolation. Battuta says they had the population and infrastructure to do more, but even so, they found the political will to build massive destroyers and assault frigates with a powerful bomber fleet to match when the only threat was a potential Shivan one, but which must have seemed very remote given the isolation. And yet they still built this fleet. These are not strict, moral pacifists. These are not flower children. And who knows (well outside the BP team) what Shambayla is? They have long range planning which yes has fostered immense economic gains and self-determination for the population, but there is an element of chess playing with people lives (including the GEFs) not unlike the Shivans and Vishnans (which makes sense given the latter's influence).
Nor is the GTA some evil military dictatorship that treats its populace like North Korea. Far from it. However, it has been stated several times that the only thing keeping the disparate Terran colonies together and from revolting against the GTVA in a new Neo-Terran Front, slaughtering Vasudans and the status quo is fear of the Shivans (I exaggerate only slightly for effect). The GTA has forged itself into a weapon, those are the terms in which it thinks. Even Steele is such. Remember the conversation he has with the turncoat Elder? He immediately jumps to Shambayla being a weapon and the Elder laughs at him, saying something to the effect, "how little you understand us" (paraphrased obviously and to be fair, I would jump to it being a weapon or fleet too
).
No doubt there would be collaborators (like the turncoat Elder), but there would also be civilian resistance to giving up their Elders to the GTA. And I don't think the GTA would respond well to it given their mentality. Again, this is not because the GTA are evil monsters, but they simply have the wrong toolset and mindset to occupy peacefully UEF-like planets. Their mentality is dealing with Shivans and the Neo-Terran Front (and related organization that have popped up since), not Henry David Thoreau. Essentially the GTA can't play their cards right, because they don't hold the right cards.
