The rationalizations for discrimination are similar regardless of the group being discriminated against. Drawing upon the research of social psychologist Henri Tajfel, Klein explains that there is a human instinct to view one’s own group with favor and outsiders with hostility. This we-they dichotomy is so deeply ingrained that it “operates independent of any reason to treat social relations as competition” (51). In experiments with boys, Tajfel demonstrated the strength of this instinct: He found that the boys would opt to reward their own group less in order to ensure that the gap between their rewards and the out-group’s rewards was bigger.

Humans evolved to exist in groups, which were necessary to survival. Exile from a group meant death. This instinct is thus embedded in human brains. Klein cites the example of sports fans, who want their team to win and make the team a part of their self-identity, even if players are traded or the team changes locations. Just like sports fans, partisans act to preserve the status of their group. They are not acting as citizens making deliberative policy choices. Elections exacerbate the team mentality, depicting the other party as the enemy and directing anger toward it, prioritizing feelings over thought.