In "Ender's Game," the protagonist Ender Wiggin navigates a complex battlefield where strategy and tactics are crucial for survival. The quote, "Since when do you have to tell the enemy when he has won," emphasizes the idea of secrecy and deception in warfare. It suggests that acknowledging an enemy's victory can undermine one's own position and tactics. Ender learns that victory is not just about physical conquest, but also about psychological advantage and maintaining control over the narrative of the conflict.

This quote reflects a broader theme in the book related to the morality of warfare and the burdens placed on young leaders. Ender's journey involves grappling with the implications of his actions and the responsibilities of leadership. By not revealing the enemy's triumph, Ender symbolizes the idea of retaining agency and power in a situation where the stakes are incredibly high. It's a commentary on the complexities of victory and the often unseen consequences that accompany it.