The sniper sat on the roof in Dublin, and listened to guns farther up the street after a long day. He knew that the enemy was somewhere in the area, but he didn't know where.
Who else is here, I wonder?
In the street, an enemy car stops below and a beggar woman comes to inform the man in the car about the position of the sniper on the roof. The sniper kills her and the man in the car, it drives away.
When the sniper shoots the car and the woman, the enemy sniper knows where he is now, and shoots our sniper in the arm.
To get off the roof, the sniper has to trick his enemy into thinking that he is dead so the enemy will stand up. The sniper drops his hat and rifle to the street below.
The enemy is fooled by the trick, and stands up, which allows the sniper to shot the enemy so he can get off the roof. The sniper then feels the effects of the war as he watches the body fall to the street.
The sniper has a curousity to know who the enemy was, and when he turns the body over in the street, he looks into his brother's face.