Here's the difference, as I see it.
To take over is outsiders coming in. Imperialism.
To take back is to reclaim what was once yours. Independence.
So, to take over, say... a city that was never yours and that you're not from, sounds to me like you're a bunch of ego-maniacal imperialists. Might as well be building a fucking fully operational battle-station.
On the other hand, to live in that same city and to reclaim it from the evil forces that control it and (by proxy) you, that sounds to me like a revolution. A rebellion of worthy allies.
Imperialists always get what's coming to them. Just ask Rome.