Cardenas’s expression did not change. “Nanotechnology is banned, you know that. No matter how you want to use it, you can’t make nanomachines anywhere on Earth. You’d have the GEC, the world government, every religious nut on Earth going crazy if you even hinted that you’re thinking of using nanotechnology.”
Humphries smiled patiently. “We won’t tell them, for god’s sake. We just start doing it. In secret. Out in the Sahara or the middle of the ocean or Antarctica, anywhere. In a year or maybe even less, they’ll start noticing the carbon dioxide levels going down. We can take out the other greenhouse gases, as well. They’ll see that the greenhouse warming is lessening. Then we’ll have them all by the balls! They’ll have to accept what we’re doing. They’ll have no choice.”
“And what happens if these nanomachines don’t work exactly right? What happens if they start taking other carbon compounds apart? Like you, for instance. You’re made of carbon atoms, aren’t you?”
“That won’t happen.”
“I know it won’t happen,” she said. “Because I won’t do it. It’s an absurd scheme.”
“What’s absurd about it?” Humphries demanded.
A slight, sardonic smile cracked Cardenas’s facade. “You don’t have any idea of how enormous Earth’s atmosphere is. Do you know how many tons of carbon dioxide you’d have to remove? Billions! Tens of billions, at least! You’d have to cover Africa with nanomachines to remove that much carbon dioxide!”
“I’m sure that’s an exaggeration,” Humphries muttered, scowling.
Cardenas shot to her feet, startling George. “All right, you’d merely have to cover the Sahara desert. It’s still beyond belief!”
“But-”
“And you’d never be able to keep it secret. Not a program of that scale.”
“But it could be done, couldn’t it?”
“It could be started,” she admitted. “Until some fanatic drops a nuke on us. Or laces our drinking water with plague bacillus.”
“I can protect you against terrorists,” Humphries said.
Cardenas paced to the window, obviously thinking furiously. Turning back to Humphries, she said, “Using nanomachines on that scale is an invitation to disaster. Some fruitcake could steal a handful and re-program them to take apart… plastics, for example. Or petroleum. Or use them as assassination weapons. You’re talking about gobblers, for Christ’s sake!”
“I know that,” Humphries said coldly.
Cardenas shook her head. “It won’t work. Aside from the sheer physical scale of the project, the authorities on Earth would never grant approval for using nanomachines. Never! And I can’t say that I’d blame them.”
Humphries slowly got to his feet. “You refuse to even try?”
“It’s a hopeless task.”
He sighed theatrically. “Well, I’ve tried to be reasonable. I thought we might be able to work something out.”
“Let me go,” Cardenas said, with a pleading note in her voice.
“I thought it would be a way for you to be with your grandchildren, as you want to be.”
“Just let me go.”
He gave her a sad look. “You know I can’t do that. It’s too great a risk for me.”
“You can’t keep me here forever!”
With a small shrug, Humphries asked, “What do you propose as a way out of this impasse?”
She stared at him, open-mouthed.
“I mean, you can see my problem. I know you can. How can I let you go when there’s every chance that you’ll tell people that I’m responsible for Dan Randolph’s death?”
“But I’m responsible, too.”
“Yes, I know. But you’d confess to it, wouldn’t you?”
“I…” she hesitated, then said in a low, defeated voice, “I suppose I would, sooner or later.”
“There you are,” Humphries said softly. “The problem remains.”
“You’re going to have to kill me.”
“I don’t want to do that. I’m not a cold-blooded murderer. In fact, I’d like to see you reunited with your grandchildren, if it’s at all possible. There must be some way we can work together, some way we can find around this problem.”
“I don’t see any,” Cardenas whispered.
“Well, think it over,” Humphries said, heading for the door. “I’m sure you can come up with a solution, if you just put your mind to it.”
He smiled as he opened the door and left. George saw the guard standing out in the hallway before Humphries closed the door and its lock clicked shut.