Perry's friend Lobel is into movies. Like, really into them. It may seem out of place, or even a little obsessive for him to talk about movies when they're supposed to be looking out for the enemy.
Beside the point, much?
But really, thinking about movies is just the way Lobel copes with war. He tells Perry as much, during a nighttime watch: "I'd be real nervous, except I know none of this is real and I'm just playing a part." (6.24) Real healthy, Lobel.
Lobel uses movies to calm himself down and feel safe—even when he's really not. On his watch with Perry, he tells Perry they won't die because they're in the part of the movie where he, as the star, is "sitting in a foxhole, explaining how he feels about life and stuff like that. You never get killed in movies when you're doing that." (6.26)
Later, when they meet a Vietnamese girl named An Linh, Lobel leads his fellow soldiers in a fantasy where they take An Linh to Hollywood and rename her Arielle to get her parts. (4.93-105)
A little racist? Absolutely. But hey, lots of movie stars don't use their actual names, and more importantly, Lobel's thinking about making An Linh seem more imaginary. Renaming her Arielle turns her into a character in a story, instead of woman who lives in a war zone and is in danger of being killed.
With movies, Lobel's doing the opposite of keeping it real. He likes his war fake and shiny.
But sometimes war is so real that it crosses over into fake and movie-like again. The more horrible things Perry sees, the more his memories feel like movies: "They just kept coming, one by one. Short movies. A few seconds of a medic putting a tag on a wounded soldier. A few seconds of a chopper taking off over the trees. A guy cradling his rifle. A body bag." (8.107)
Now that's a montage you don't want to be a part of in real life.
Perry's cinematic flashes are a little different from Lobel's movie fantasies: Lobel's are more of a choice for getting through the days, while Perry's seem like a mental reaction to war.
In that way, Lobel's strategy for dealing with war becomes Perry's, too, in a slightly different way. Perry's brain stores his more awful war memories and replays them like short movies. If they feel fake, then Perry doesn't have to think about them —or be depressed by them—quite as much. That way, he can just imagine giving them a mediocre rating on Rotten Tomatoes and moving on with his life.