Most good stories start with a fundamental list of ingredients: the initial situation, conflict, complication, climax, suspense, denouement, and conclusion. Great writers sometimes shake up the recipe and add some spice.
Exposition (Initial Situation)
Can't Hardly Wait
Except, war is scary. Waiting is better than fearing for your life in battle after battle.
That said, Perry does have to wait a whole lot on his journey to Vietnam. He, his new friend Peewee, and a quiet-ish nerd named Jenkins spend a bunch of time being shuffled from a plane out of Anchorage to a Japanese airport to another plane to an airport in Tan Son Nhut to barracks to a truck to Chu Lai.
They know they're going to war, but they don't know what's about to hit them. In this case, the waiting part might be better than the being there.
Rising Action (Conflict, Complication)
Enemy Face-Off
Perry, Peewee, and Jenkins join a platoon and replace men who died. Encouraging start. When the platoon goes on its first patrol, it's Perry's first time looking for and trying to hit the enemy—and his first time watching a fellow soldier die. All of a sudden, war gets real.
Each patrol duty and each mission, Perry's whole identity gets shaken by the war. He gets closer to his platoon, has to watch some of his friends and mentors die, and comes close to death a few times himself. Even when Perry's in a hospital, away from combat, getting a not-too-bad wound treated, he can't really enjoy his time off. He knows he has to go back in and keep risking his life. Scary stuff.
Climax (Crisis, Turning Point)
Just the Two of Us
But not in a romantic way. More in a separated-from-our-squad-how-are-we-going-to-survive kind of way. True, it wasn't like being with the squad guaranteed protection, but at least that way they had a radio to call a chopper to get them out of combat. Peewee and Perry know they don't stand a chance against the huge number of Vietcongs in the area, so they spend a very harrowing night in a hole, hoping no one finds them. It really is amazing that they make it back alive.
Falling Action
Injury Jackpot
Not two words you usually think of together. But Perry and Peewee's reaction—being happy about their injuries—shows you just how much they don't want to fight in the war anymore. Luckily, their injuries are minor enough that neither of them die or have a limb amputated, but major enough to send them home. Monaco doesn't have the same out, though. He drinks with Perry and Peewee for a couple days, then leaves to return to the platoon. Sorry, Monaco.
Resolution (Denouement)
The World
Perry and Peewee leave Vietnam on a jet plane, planning never to return (and it's hard to blame them). The book doesn't show what their life is like when they're back home, but it's pretty clear it'll take some adjusting. The weirdness of being on a civilian plane is enough to make Peewee's hands tremble and to make the guys clutch hands. Will they ever truly be able to leave their time in Vietnam behind them?