Stormcloaks Or Empire (One Of The Three Certainties Of Life)

[veti]

Yall are aware that there is a lot of room between "vassal" and "completely free of any influence at all" right?

Influence != Authority. The Dominion has (because it claims it and, damningly, the self-styled Empire does not dispute that claim) authority over what goes on in Imperial lands. The Thalmor have their own enforcers, their own prisons, their own torturers in Skyrim, who operate with the full-throated blessing and support of the supposedly-defending imperial forces. They have patrols across the land who will accuse and attempt to murder innocent passers-by with no trial or evidence whatsoever, and the legion supports them while they do it.

Oh sure, Tullius mutters a bit when he's sure no Thalmor are listening, but when Elenwen says "jump", all he says is "how high?"

Just between you and me, a lot of what Ulfric says about the Empire is true.
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The Thalmor invited me here to remind everyone that they can tell the Empire what to do. I would refuse, but I don't want to jeopardize the peace between us.

The Empire is not a vassal.what they are is under a specific treaty as a result of getting their butts handed to them in a war. The Dominion's ability to enact policy is limited to making sure the terms of the treaty are followed, and even then their de-facto power in actually doing so is quite small.

"The terms of the treaty" are effectively rewritten on a regular basis to make sure they cover whatever the Thalmor happen to want. Justiciars into Skyrim? - that wasn't in the treaty when it was signed, but somehow it is now. Tullius to go to Elenwen's parties, to make sure everyone knows who's boss? "Thank you ma'am, may I have another?"

You're right on one point, that the de facto power of the Thalmor is quite small. But that hardly matters, when they have the de facto and de jure power of the Imperial legion doing their dirty work for them. That's the genius of Thalmor diplomacy, again. The "Empire" is psychologically so whipped, they're now actively participating in their own subjugation.