In A Separate Peace, what is significant in Leper's change of heart toward the war?

Leper's change of heart after seeing the film of the ski troops (ironically not American soldiers, at all), is significant for another reason, as well. It emphasizes the private fear that all the boys feel as the year wears on, in terms of their own participation in the war. Leper enlists after seeing the film because, as Gene says, Leper had found a "friendly face" to the war. He thought he had found a way he could stand up to and survive what was coming for all of them. As Devon's "first recruit," Leper was the first to reveal just how afraid he really was by acting in a way that he thinks will stave off destruction. He was wrong, of course, with tragic results.

This fear of not being able to meet the challenge of military service, the fear of failing as well as dying, was seen also in Brinker. He dressed like a soldier for a time and sometimes wrote sarcastic poems about the war as a means of covering up his fear. He made plan after plan to enlist, but never did. He thought of service in the Coast Guard as a refuge, a plan his father rejected as cowardly. Like Brinker's various strategies, Leper's change of heart was an attempt to prevent or control the uncontrollable.