If his true motives are protecting Azeroth, then he will have done what his father could not. Remember, Deathwing wasn't inherently evil, and thus in a way can't fully be blamed for the atrocities he committed.
Either way, he is forging his own path in spite of his father, and in doing so will either redeem his father or continue his legacy, depending on where they take his character.
Slaying 8bit dragons with 6 pixel long swords since 1987.
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