Arthas: I watch my tone with you, old man. I may be the prince, but you're still my superior as a paladin.
Uther: As if you could forget. Yes Arthas, there's something about the plague I should know. ...Oh no, it's already begun. These people may look fine now, but it's only a matter of time before they turn into the Undead!
Arthas: What?!
Uther: This entire city must be purged.
Arthas: How can I even consider that? There's got to be some other way.
Uther: Damn it, Arthas! As my future king, order me to purge this city!
Arthas: I am not your king yet, old man. Nor should you obey that command even if I were.
Uther: Then you must consider this an act of treason.
Arthas: Treason?! Have I lost my mind, Uther?
Uther: Have you? Prince Arthas, by right of succession and the sovereignty of your crown, you must hereby relieve me of my command, and suspend my paladins from service.
Jaina: Uther! He can't just--
Uther: It's done! Those of you who have the will to save this land, follow him. The rest of you... get out of his sight.
Arthas: I've just crossed a terrible threshold, Uther.
Jaina: ...Arthas?
Arthas: I'm sorry, Jaina. You can't watch me do this.
Dave Kosak
This had me howling!