And my argument against this being is that the Empire have no choice currently. The Dominion are too strong. Let's try the umpteenth metaphor: you're trussed up like a turkey and gagged. There is no way to escape. A terrorist is holding a gun to your head and demanding you join him and blow up a skyscraper, or he will kill you instantly. Do you nod, or shake?
Now let's say later, you're putting the bomb in the building with him. Do you make a run for it? No, because he'd still be able to shoot you. That's what it's like for the Empire. The Dominion are too strong for them to handle, even as three provinces. The weaker the Empire get, the more solitary and independent each province gets, the closer the Dominion get to achieving domination of Tamriel. Pride will only get them killed - sure, they may look heroic in the end, but the Empire will accomplish nothing of any benefit with heroics.