Answer: "Unit, Corps, God, Country"
Kaffee is asking the two Marines standing trial whether they assaulted Private Santiago with the intention of killing him, and the response that they only intended to train him. When Kaffee asks, "Train him to do what?" Dawson replies, "To think of his unit before himself. To respect the code." The code is, of course, "Unit, Corps, God, Country." Kaffee is stunned by this and responds, "The government of The United States wants to charge you two with murder. You want me to go to the prosecutor with: 'Unit, Corps, God, Country'?" Dawson says, "That's our code, sir."
Wolfgang Bodison is the actor who plays Lnc. Cpl. Dawson, and director Rob Reiner cast him even though he had never acted before. Bodison had been serving as Reiner's personal assistant, and when Reiner started pre-production on this movie, Bodison was helping him scout locations for the film. But Reiner liked his look so much (and felt he fit the image of a hard core Marine) that he gave him a pivotal part in the movie.