Not everyone is meant to be happy, not all lives have the equal chances as others. Some lives are naught more than a sacrifice for the betterment of others.

Slaying Nidhogg would free Ishgard from its thousand years of suffering, it would end this bloody war and no one else would be made to suffer for it. Orphans would no longer be turned into soldiers, forced to face the fangs and claws of these fire breathing demons that slew their families. No longer will these fiends destroy villages, massacre innocents--or, at the very least the beasts will be less bold once their sire falls. Like vermin without direction, they will scatter to the wind, and we will be able to eradicate the vile monsters.