If I explained his mindset, I'd be ruining the fun :P As soon as you understand his character motivation, it becomes a little boring.

Edit: Woah there Mr Scarend, You would not be able to muster an army and attack a city in a few hours if you were banking on Peaceful negotiations. The logistics alone make it impossible for you to reach Sanchal in such a short time. You also gave no chance for any defence and you completely ignored the fact that the Argonians would have a time to land by then.