In Joseph Heller's "Catch-22," the protagonist Yossarian offers a poignant insight into the nature of enemies in wartime. He asserts that an enemy is not just the opposing side but anyone who poses a threat to one's survival, highlighting the arbitrary nature of allegiance and danger in conflict. This perspective challenges the conventional view of enemies in war, suggesting that even those on the same side can be harmful.

Yossarian's statement emphasizes the importance of self-preservation over blind loyalty. By identifying Colonel Cathcart, a figure of authority, as part of the problem, he underscores the chaotic and often absurd reality of military bureaucracy. In essence, the quote serves as a reminder to be vigilant about the true nature of threats, which can come from unexpected sources, reinforcing the theme of individual survival amidst the madness of war.