for Casualties of War by Chris Lynch
Morris, Rudi, Ivan, and Beck are best friends for life. So when one of the teens is drafted into the Vietnam War, the others sign up, too. Although they each serve in a different branch, they are fighting the war together -- and they promise to do all they can to come home together. Of the four, it's Beck that has the most to lose. He's the smart one of the bunch, and he could be -- SHOULD be -- going to college. His parents certainly think so. But he has a pact to honor, and so Beck enlists in the US Air Force. As their tours of duty near completion and the war itself spirals further out of control, the four best friends are at last on a collision course. Will they all survive long enough to be reunited?
Publisher description retrieved from Google Books.