"Captain Crichton," said the Lieutenant, as he entered the captain's office.
"Formal as always, Binben," commented the captain, looking up from and setting aside some paperwork. "What can I do for you?"
"I have a request..." began the lieutenant, before approaching the desk between them and placing the request upon it. "I would like to leave the opera and return to the earth."
Captain Crichton did not even deign to look at the request. "I won't authorize this."
Binben was genuinely confused by this. "On what grounds?"
"I have no grounds."
"I can always appeal the decision. And if you have no grounds for refusing me this, then you will likely get a mark on your record."
"And in the ten years that you've been captain, five people have asked to go back to Earth, and you've approved their requests without issue."
"I know that, too," replied the captain, rising in anticipation of what might come next.
"But then why won't you authorize my request?"
"Because you are my son, Binben," returned the captain. "I know that I cannot stop you, but I can at least slow you down. There is nothing for us on Earth--"
"And yet whenever we send people back, nobody wants to return. The only time that anyone has ever come back was when they chicken out at the last minute; nobody actually on the earth ever wants to come out here--"
"And they couldn't even if they wanted to," answered his mother, her rage silencing Binben. "At this point, there's no way that we could possibly ensure our safety against anyone from the planet."
Binben was dumbfounded.
"That part's secret," she said. "It's above your rank. It doesn't matter, though: Nobody wants to come out here, from there. Honestly, banning anything with code in it from the return trip is probably a more significant safety measure."
She resigned herself to this: All that she could do was tell him, and let him decide for himself. "You're too young, of course. You haven't seen it. You weren't there on the last day. The nanotech on Earth changes people, and for the worse. You won't want to come back out here because you won't even think of it. You'll be too busy in the illusory worlds. And if you do think of us, then you'll pity us, wondering how we could live like this, when Earth is so much better. And by the time that you might think to somehow leave while leaving it all behind, to visit here despite all of its limits, you won't think it worthwhile - if there even is still a "you" - since we'll all be dead. You won't want to leave because you won't be you; as far as I'm concerned, those who returned to Earth before you sent themselves to their deaths."
Author's note: It didn't come up in the story, but Binben Crichton's schoolyard nickname was "Browder". You'll get it.