The theme of paranoia is also prevalent in Little Brother. Most citizens of Cory Doctorow’s dystopian San Francisco are all constantly in fear of being arrested or detained- the exceptions being busybodies and whistle blowers. When Marcus creates the Xnet, he creates the system because he knows he is in danger of getting caught for his activist movements and his exposing the Department of Homeland Security. The same is the case for the other people who join his rally to overthrow the DHS in their city- they are protesting in the name of what is right, but they know that what they are doing is punishable, so they are always looking over their shoulders.
To further illustrate the existence of paranoia as a theme in Little Brother, one may look to the instance in the novel wherein Marcus, operating later on in the book under the screen name M1k3y, is asked to do interviews by several newspapers and radio shows- in response, he instructs them to log on to Xnet so he can host a press conference through one of the Xnet games. It is evident through this section of the book that Marcus does not want to be exposed as the leader of the underground movement, as he does not wish to face the consequences of his actions, even though he knew he was in the right. He takes these kinds of precautions because he is afraid, or paranoid, that the DHS will expose his true identity and his quest for justice will be put to an end.