How can war turn the most docile of men into a ferocious beast?
How can war blind the most rational individual?
Bloodshed. Pain. Fear. Rage and thirst of revenge for those who fell on the battlefield were fueling a feud that was never going to be left behind. If even when the Legion was invading Azeroth, Horde and Alliance were unable to put their weapons away and see reason, Lord Dawnlight knew that there was little hope for him to live long enough to see the end of such pointless conflict.
While he was the first one who desired peace for his Kingdom, there was nothing he could do but answer the calls to arms. The humans were still unable to accept the destruction of Lordaeron and the region's "new" rulers; Stormwind marched north in the attempt to rebuild a handful of cities in the Plaguelands, killing Horde forces on the way. The reaction didn't come late, and now Redridge was under siege.
An unwanted but necessary manoeuvre, to remind the humans and their lapdog allies their place.