What is Cooper experiencing if he believes his phone line is tapped and avoids predictable routes?

Cooper's belief that his phone line is tapped indicates a specific irrational suspicion that others are out to harm him or are monitoring him without justification. This state of mind aligns with delusions of persecution, which is a type of delusion where an individual firmly believes they are being targeted or victimized by others. The avoidance of predictable routes further demonstrates his fear and attempts to protect himself from perceived threats, which is consistent with feelings of being persecuted.

While paranoia could also be considered in this context, it is generally part of a broader spectrum of symptoms that involve anxiety and distrust. In this scenario, the emphasis is on the belief of being targeted rather than a more general sense of distrust associated with paranoia. Generalized anxiety disorder and obsessive thoughts do not typically encompass the kind of firm, false belief in persecution that Cooper is experiencing. These distinctions clarify why delusions of persecution is the most fitting description in this case.