"In Kislevite culture, tyranny is not condemned. As long as a monarch possesses sufficient capability to rule, the Kislevite serfs will willingly serve as beasts of burden for him to enslave."
The Iron Tsar spoke slowly, his voice exceedingly calm, as if he were discussing philosophy with his progeny rather than the grave matter of massacring prisoners.
"I have heard of this. Before the Legion arrived at your home world, I had heard rumors. The Kislevites are indeed a race of silent endurance; it is quite remarkable."
Hearing his gene-father speak of his home world's conditions, Forrix nodded slightly and spoke.
"The Kislevites so welcome autocracy and tyranny that it is even reflected in their monarch's title—'Tsar and Autocrat.'"
"Look at them—these simple Kislevite serfs so welcome a brutal yet wise ruler to govern them that they specifically use the term 'Autocrat' to describe their sovereign."
Ignoring his First Captain, the Iron Tsar continued to explain the culture of his home world to his scion, word by word.
"Forgive my ignorance, my Lord. We were discussing why you chose to slaughter those prisoners of war. Does that have a significant connection to Kislevite culture?"
"I believe it would be better to clarify this. After all, Lord Dorn—another Primarch—is already extremely dissatisfied with your actions, my Lord."
At this, Forrix could not help but show a trace of confusion and bewilderment. He spoke cautiously to avoid provoking Perturabo's ire.
"Of course it is related, because Kislev taught me one thing: the victor is not condemned."
"Yes, according to the 'war ethics' that Dorn adheres to, my deliberate slaughter of those resistors—the old, the weak, the women, and the children—is a display of zero moral standing."
"But he forgets one thing: the essence of war is devoid of morality. Yes, when war is contained within a certain scope, everyone can maintain a shred of a 'bottom line.' People can politely protect civilians and prisoners, using so-called 'conventions' to regulate it all."
"But when war reaches a fever pitch, when every single person is inseparable from the conflict, these so-called war ethics become irrelevant. Because, by then, the distinction between civilian and soldier is negligible."
"Forrix, think carefully. When civilians are conscripted into munitions factories to manufacture weapons for the army, do you believe they are truly 'unarmed'? Should they be protected by both armies?"
"If you call them civilians, they are providing supplies and weapons to the enemy; if you call them soldiers, they have not truly taken up arms or donned uniforms to fight the enemy on the front lines."
Facing Forrix's inquiry, Perturabo briefed him with a calm composure. Though the Iron Tsar's words were relaxed and effortless, he was discussing an extremely grim subject.
"This—"
Hearing Perturabo discuss the ethics of war, Forrix, the First Captain of the Iron Warriors, could not help but look shocked and lost.
As an Astartes, he had never been encouraged to overthink such matters; he had never pondered the things "clever men" think about.
Seeing his First Captain standing there like a wooden statue, the Iron Tsar sighed softly, as if lamenting that his scion's mind could not keep pace with his own. Then, he slowly continued.
"You see, Forrix, the 'war ethics' Dorn insists upon are difficult to justify at this point. When war descends into what the ancient Terran sages called 'Total War,' those ethics cease to exist."
"In a standard confrontation between two armies, one can still discuss war ethics, trying to protect civilians and treat prisoners well. But when the scale of war expands without limit, when everyone from civilian to soldier is embroiled in the conflict, the primary goal becomes: destroying the enemy's war potential, leaving them incapable of fighting again."
"At that point, even genuine civilians will be put to the sword, simply because they are the future manpower for the army. You cannot give them that chance."
"That is the nature of war, Forrix—a monster that devours everything. And I? I simply saw through it all early on and embraced it."
"Thus, I chose to destroy the enemy's effective strength and slaughter their viable population, leaving them unable to resist for decades or even centuries. Dorn fails to see this; that is his loss."
"Ultimately, the victor is not condemned. This has been a self-evident truth since ancient times. I suspect that even if Dorn reports this to the Emperor, the Emperor will not blame me. Because I conquered in the shortest time a world that Dorn was stuck in a stalemate with."
Perturabo narrowed his eyes slightly, delivering his long discourse to Forrix.
Listening to his gene-father's words, the First Captain of the Iron Warriors broke into a cold sweat. Based on all his past experience, Perturabo had, unfortunately, hit the mark.
Every one of the Fourth Legion's previous, unimaginably cruel siege wars had ended in massive local population loss. Whether intentional or not, it was unavoidable.
Out of his morality as an Astartes, Forrix himself was unwilling to dwell on the implications, but today, his gene-father had ruthlessly stripped away the veil, revealing the bloody reality.
"Now, Forrix, is there anything you still do not understand? Do you understand why I treated the resistance there in such a manner?"
Perturabo looked at Forrix, his eyes narrowing slightly as he asked slowly.
"Yes, I understand. However, I have one last question."
Forrix slowly raised his head to look at his gene-father and asked in return.
"What question?" Perturabo asked.
"That is... are you not afraid that the other Primarchs will distance themselves from you because of this? After all, deliberately massacring prisoners is never a good thing—"
Forrix frowned slightly and spoke his question slowly.
"Heh. I assure you, aside from Rogal Dorn and a few brothers who might have a 'moral fetish,' no one can be bothered to care about such things."
Hearing Forrix's concern, Perturabo let out a cold laugh before speaking.
"Now, tell me, where is our next objective? Where is the nearest world that has not yet submitted to the Imperium?"
Perturabo spoke again, his voice filled with an ambition that hungered for war and conquest.
"My Lord, it is—Olympia. A world discovered by Rogue Traders. The locals call their world Olympia."
Hearing Perturabo's inquiry, Forrix did not dare delay and answered quickly.
"Olympia... what an interesting name..."
"Then, for our next step, let us pay them a visit. Let's see if the natives there wish to submit to the Imperium peacefully. Sometimes, I too want to manage a few cases of peaceful integration, to let the whole world know I am not some bloodthirsty warmonger—I only do what I deem 'necessary'."
Hearing Forrix's report, Perturabo nodded slightly.
"As you command, my Lord."