i need some help with the given topic-
"describe with close reference to the story (sniper-liam o'flaherty) how the sniper pays a heavy price for committment to republican cause"
Let's consider for a moment that the word "brother" is not meant in a literal sense. O'Flaherty leaves this ambiguous. Quite possibly the sniper has identified with the man he killed as a "brother" in circumstance. Both young, both dedicated to their country, both driven by their sense of right and wrong. Yes the sniper might have paid the price by killing his own brother, but in addition if this was a "brother" of affinity, then the sniper paid the price by killing someone identical to himself and thus killed a part of his own self.
The most obvious answer to this is that the sniper ends up with a bullet wound in his right forearm and a dead brother. Because of his dedication to the cause, he is up there on the roof as a sniper. First, this causes him to get shot. Then it causes him to shoot his opponent, who he later finds out is his brother.
Therefore, the sniper pays a price physically (he gets shot) and especially emotionally (he will have to deal with the idea that he has killed his own brother) for his commitment to the cause.