"No imagination whatsoever," remarked the scientist. "It's the same with all of you service people. That can't happen to me." He paused. "But it can. And it certainly will."

"I suppose I haven't got any imagination," said Peter thoughtfully. It's—it's the end of the world. I've never had to imagine anything like that before."

This dialogue between John and Peter occurs when they are coming back from the first mission in Chapter Three. John accuses Peter and rest of the military of using weapons of mass destruction without ever realizing that these weapons could one day be turned against them. He accuses the military of creating a dangerous situation but lacking the foresight and imagination to see where their actions can lead them. Just earlier, the two men have been speaking about how the Russia and British sold airplanes to countries who ultimately used those same airplanes against them.

Peter is obviously aware of the existence of weapons of mass destruction, but never once believed such weapons would actually be used. Peter is an ordinary soldier and an ordinary citizen; Shute wants us to relate to Peter so we will take the novel's warning seriously. Shute believes that if such dangerous weapons exist they will be used, either deliberately or accidentally. On the Beach is written in an almost educational tone, aimed at people like Peter who cannot imagine the end of the world. Shute takes care of the job for us, filling in our imagination with his own vision. This specific passage challenges us to see if we can still refuse to imagine the end of the world and refuse to think about what we can do to prevent such an event from happening.