That's the logic of monsters:

Step 1: We believe the enemy is a monster who does [terrible act].

Step 2: To counteract this, we must do [terrible act].

Result: we maintain we are the "good guys" because we were "forced" into it by their presumed behavior.

He who fights with imagined monsters should look to it that he himself does not become a monster. And if you gaze long into an abyss, the abyss also gazes into you.

That quote is 140 years old. Is that enough time to heed it?