"A gate to what is basically hell in our Land?"
Nords-"Close it!"
Dunmer-"Close it!"
Imperials-"CLose it!"
Argonians-"Demons invading our swamp? No don't close that gate, we are invading hell!"
Then after having been winning in Hell, the Daeric Prince eventually closed the gate himself since the Argonians were actually taking over his Daedric plain.
Argonians-"Hey, we totally *** over those Demons, the Demons kicked the **** out of Dunmer our former slavers. If we are better than demons, and demons are better than Dunmer, we must be way better than Dunmer. Invade!"