"The Sniper" shows a gradual change in the protagonist from being a fanatic to becoming a sensitive human being. Justify this statement.

I actually have to disagree with this statement. There is
nothing "gradual" about the transformation that occurs in the protagonist of this
excellent war-time tale. Rather, the change that he experiences is sudden and is
suffered ironically as a result of his victory over his anonymous opponent. It is ironic
because we would expect for such a "fanatic" who is evidently experienced enough to not
be phased by killing others in cold blood to be overjoyed at his victory and his cunning
over his opponent. Instead, note how the text indicates that his change is sudden and
unexpected. Having watched his enemy fall from the opposite roof and land on the floor
with a thud, the sniper experiences a sudden, biting
remorse:

The
sniper looked at his enemy falling and he shuddered. The lust of battle died in him. He
became bitten by remorse. The sweat stood out in beads on his forehead. Weakened by his
wound and the long summer day of fasting and watching on the roof, he revolted from the
sight of the shattered mass of his dead enemy. His teeth chattered, he began to gibber
to himself, cursing the war, cursing himself, cursing
everybody.

Thus we can see
that the undoubted change the sniper experiences is not gradual, but sudden, and seems
to show that the "fanatical" face of the sniper has broken down after the release of
tension following his own victory over his anonymous enemy. The discovery of the
identity of his enemy seals this transformation.