As a result of her extensive research into the social and economic costs of racism in America, Heather McGhee concludes that most white people adopt what she calls a zero-sum paradigm.
In this specific context, the zero-sum paradigm refers to the widespread belief among white Americans that gains for people of color are losses for them. In other words, they believe that if people of color secure better housing, more jobs, and greater opportunities, those gains will come at the expense of white people.
McGhee strongly challenges this notion. She argues that people of all races are better off if they come together and work for a common cause. Even though a large number of white people may believe in the zero-sum paradigm, McGhee convincingly argues that they are not really better off as a result, economically, socially, or morally. In actual fact, it's only a small minority of wealthy, powerful individuals whose interests are furthered by the paradigm.
As McGhee points out, the logical extension of the zero-sum paradigm is that an America without racism is something that white people should fear. As white people will see the gains of people of color as a loss to them, they will increasingly come to regard society as having nothing good in it for them. As a consequence, they will become more alienated from society, holding on to their guns and their racial identity with equal tenacity.