I think that part of the tension that is established in chapters 4 and 5 is the direct nature of the discussions between the American and Changez. Interspersed within the reveries of Manhattan and Erica are some fairly pointed discussion points that reveals the gap of cultural differences, and perhaps political ones, between both. The discussion of the scar to open chapter 4 is something that Changez broaches using the direct insinuation that his scar is somehow terrorist related. The way in which Changez tells the American to relax and not be so jittery over the power outage is another example in which tension begins to build because we, the reader, realize that Changez and the American are there with separate narratives and perhaps, separate purposes that are mutually exclusive with the other. The discussion of bats to open chapter 5 is another example of how the American sees reality in one way ("Creepy") while Changez sees it another. The emerging disconnect between both how both perceive reality is a way in which the tension begins to emerge between both characters.