He was gripping the edge of the bed now, glaring at her. "A
civilization that could discover time travel and build robot factories
wouldn't find it hard to send a ship to Mars!"
"A _ship_? Oh, you mean something like a _vliegvlotter_. Why, no, I
don't suppose it would be hard. But why would anyone want to do a
thing like that?"
He was on his feet towering over her, fists clenched. She raised her
arms as if to shield her face if he should hit her. "Let's get this
perfectly clear," he said, more harshly than he realized. "So far as
you know, no one has ever visited the planets, and no one wants to. Is
that right?"