Anyone who’s tried to shoot a sawed off shotgun from a bicycle knows how right you are. Thinking about the highway scenes in Octavia Butler’s Parable of the Sower and my own run-ins with gangs of street urchins in Berlin, you’re also vulnerable to attack on a bicycle in a way that you’re not in a vehicle or even on a horse. Post apocalyptic literature is as much about the fear of being hunted as being the hunter.