HOW DOES GRAFF ISOLATE ENDER FROM THE REST OF HIS LAUNCH AND WHY?

 Two voices are discussing Ender's incident on the flight. Graff seems to be one of the two, since the other commends him for allowing such a thing as a broken arm, even though Graff insists that it was an accident--it was too strong a reaction, and it made the other kid into a hero. Ender might be too isolated now. But they realize that they can do little for him, because if Ender comes to believe that anyone will ever help him out, he's "wrecked." Ender needs to know that there will never be an "easy way out," or else he will not become the commander they need for the upcoming war. Ender must be separated from the boys so he does not have allies or friends.