What do you think likely happened to Cardassia Union after the Dominion War? Would all 3 of the victorious powers have occupied Cardassia Prime after the war? Would the Cardassians have their own sovereign state right after the war? I would assume the Federation would want Cardassia society to be more Democratic so that they would abandon the oppressive and militaristic policies the previous regime had in place.
However if all 3 powers are occupying the planet, what's to say the Klingons or the Romulans wouldn't want to set up puppet governments in their occupation zones? Look what happened with Germany after WWII, both the USSR and the Western Powers set up different governments in their occupation zones.