Re: Star Trek Insurrection the Dominion War??
The general public didn't need to know exactly what the Dominion was on TV, only that the condition of war existed already, and the story would have been self-contained but on a larger canvas. I feel the interest of the three-tiered enemy, it's ships and tech and greater inherent gravity in-universe would be apparent.
It is far better to grasp the universe as it really is than to persist in delusion, however satisfying and reassuring. Carl Sagan