Where does O’Brien take his daughter Kathleen in Vietnam?

Explanation:

In Vietnam, O’Brien takes his daughter Kathleen to the city of Quang Ngai, specifically to the village of My Lai. This visit holds great significance as it is the location where O’Brien, as a soldier during the Vietnam War, witnessed and participated in the infamous My Lai Massacre. By bringing Kathleen to this site, O’Brien seeks to impart upon her the gravity of the past, sharing a deeply personal and haunting chapter of history while also striving to ensure that its lessons are not forgotten or repeated.