User blog comment:Thedoucheinthenorth/Skyrim alignment charts-verdict?/@comment-4975504-20120801124732/@comment-4586417-20120804151617

Obviously the nords can be beaten biy the Dominion because skyrim was a part of the empire and the empire lost. Now the empire is trying to regain its strength to fight the Thalmor once more, but since Ulfric started the civil war he's spreading the empires forces too thin. So he is accidently indirectly opening the door for the Dominion to conquer Tamriel.

And The Stormcloaks attacked Whiterun beacuse Balgruuf REFUSED to be on a side. So Ulfirc gave him an ultimatum, Join Stormcloaks or be counted as imperial, even though he isnt really, and die. Even though it is obvious he leans toward Imperial, he's still Neutral.