The quote reflects a haunting awareness of past trauma that lingers in the background of daily life. The narrator suggests an underlying tension, as if they and those around them are in a state of anxious anticipation for a catastrophe, only to realize that such an event has already transpired. This realization creates a sense of unease, illustrating how past events shape current perceptions and emotions.

In McEwan's "The Cement Garden," this feeling of waiting and realization emphasizes the theme of coping with loss and the impacts of tragedy. The characters are caught in a psychological space where the past continually influences their present, highlighting the complexities of grief and memory in their lives. The unsettling acknowledgment of an already occurred terrible event enriches the narrative's exploration of human emotions and relationships.