Warrior's Realm. The Warrior Chronicles, #3

Facing both an unknown enemy that can turn planets into crystal and enemies within his own government, Cortland Addison must unite Earth to defend a coalition of planets it can never join. As Addison navigates the morality and justice that force him to kill billions, he also battles to protect the survivors of his own onslaught. Ultimately, personal mores and a sense of duty force him to assume his destined role as War Incarnate.
Together with Bazal, the last of an ancient species of octopods, Cort must find the balance between his own realm, one of death and vengeance, and the peaceful existence that has led the rest of the galactic arm to the brink of extinction. It is against this backdrop that Cort faces his own past, to ensure that it cannot destroy his family yet again. Warrior's Realm is the journey not only of Cortland Addison and his wolves, but also the beginning of humanity's journey to the stars.