Mulder: What is this?
X: Data from a top secret military project. Borne of the idea that sleep was the soldiers' greatest enemy.
Mulder: Of course. Someone was conducting sleep deprivation experiments on Parris Island.
X: Not deprivation, eradication.
X: Why else? To build a better soldier. Sustained wakefulness dulls fear, heightens aggression. Science had just put a man on the moon. So they looked to science to win a losing war.
Mulder: And Willig and Cole were the lab rats.
X: Lab rats with the highest kill ratio in the marine corps. 4,000 plus confirmed kills for a thirteen man squad.