It does suggest this through most of the story, but it leaves open the possibility that this sense is not completely eradicated. Throughout much of the story, the sniper does not really see his targets as human beings. They are just targets to be shot. He is cold and calloused. But at the end of the story, when he finds he has killed his brother, we can imagine that this crust falls off his humanity and he regains his ability to care about others.
So, the answer to this depends on how you think the sniper himself will react to the fact that he has killed his brother. If you think that he will not really be affected, then war has killed his entire humanity and his ability to care about others.
I had to edit your original question because it didn't really make any sense, so I hope I have managed to capture what you were asking. If not, please respond to this answer with any ammendments you wish to make, but I hope I am able to respond to what you wanted to ask.
It is clear that war is presented as a transforming force in this excellent short story. Obviously the principal way that this is shown in the protagonist, the sniper, who is described as having the face of a student, as it is "thin and ascetic," but whose eyes have "the cold gleam of the fanatic." We are presented with a character who has been transformed, and not for the better, by the forces of war. He is a man who commits horrendous acts of cold-blooded murder in the name of this war, as the following act of violence demonstrates:
The turret opened. A man's head and shoulders appeared, looking toward the sniper. The sniper raised his rifle and fired. The head fell heavily on the turret wall. The woman darted toward the side street. The sniper fired again. The woman whirled round and fell with a shriek into the gutter.
In the name of the "cause" that the sniper is fighting for, he is obviously able to justify the murder of a soldier and an old woman who has been acting as an informer. War is shown to distort normal human emotions and values, as is shown through the grim and shocking ending. Through his participation in the war, the triumph that he gains over his enemy is actually a tragedy, for that enemy turned out to be the sniper's brother.