In the last chapter of A Separate Peace, Gene states that
it seemed clear that wars were not made by generation and their special stupidities, but that wars were made instead by something ignorant in the human heart.
This war within the human heart involves an attempt to ward off a perceived menace by developing a particular frame of mind, Gene continues. Thus, the war within an individual parallels that of the war among countries. With World War II as the backdrop of the personal wars going on among the boys at Devon School and within Gene, there are attacks upon enemies in both settings, and in both settings all but Phineas, who knew no fear in his innocence, there were symbolic Maginot Lines of defense set against the perceived menace, or enemy. Only Gene's war ends before he goes on active duty: "I killed my enemy there [at school]." Others, such as Leper, lost themselves in the world war, not the personal war. Truly, in A Separate Peace, the war of the world and the war at Devon School are reciprocally symbolic of each other.