You must have missed the Warsong Gulch Battleground, Garrosh’s invasion of the Night Elves’ lands, and the War of the Thorns.
And they didn’t, because these are the more important lines that you are willfully ignoring:
- Dath’Remar did not agree. He had no wish to war against a people who posed no threat to his kind.
Ultimately, Dath’Remar chose to lead his people away from Tirisfal to avert violence and spare them from further calamity.