In My Struggle Part 2, for the third time in X-Files history, Fox Mulder held a gun to the head of the Smoking Man. And once again, he failed to pull the trigger. Say what you want about Mulder being the "good guy" and above such things, but it's not as if he hasn't killed men before. He's more Han Solo (Han Shoots First version) than superhero, yet he continually lets the bad guy live. Maybe it's just that hard to shoot the devil when you're looking right at him. Maybe he really thinks that the Smoking Man can somehow stop the plague he has set into motion. In any case, he couldn't shoot him over Scully's abduction, he couldn't shoot him when colonization was set to start, and he couldn't shoot him over a plague that was shutting down everyone's immune system, including his own. Weak, Mulder.