BTW, I love how every single modern philosopher get's the mission wrong. It was written briliantly not because "did you know you didn't have to shoot? You did so yourself..." but because even after you shoot everyone you meet, it doesn't matter. You get the bullet too.
That betrayal was gut punching. (no pun intended) in a way, that only games can show. You felt the weight of the entire mission collaps on you knowing, that you were just another pawn in someone elses plan, and that you were alive only, because someone else wanted to use you one more time.