What is the epiphany in the sniper?

In "The Sniper" by Liam O'Flaherty, the epiphany occurs when the protagonist, after successfully killing his enemy, discovers that the man he shot is actually his own brother. This shocking realization forces him to confront the devastating consequences of civil war and the futility of violence, highlighting the tragic impact of conflict on personal relationships and humanity as a whole. The moment serves as a poignant commentary on the senselessness of war and its ability to pit loved ones against each other.