In my opinion, he is pretty ambivalent about what he is doing. By that, I mean that he cannot really make up his mind. At times I think he is fine with what he is doing, at times I think he is not.
I think he is fine with what he is doing, for example, when he kills the woman who has been informing. He would not have needed to do that and no one would have known if he had not. So he must have done it because he really approved of what he was doing.
But then after he shoots the other sniper, he gets all freaked out and feels remorse. That makes it clear that he doesn't always approve of what he's doing.
And I imagine that at the end of the story he's pretty unhappy with it...