The Pedia article titled 'Behavioral immune system' is a brief and informative read. I qoute below from the 'Implications for human behavior' section (bolding mine);
Within the psychological sciences, there is extensive research linking the behavioral immune system to a variety of prejudices—including prejudices against people who aren't actually diseased but are simply characterized by some sort of visual characteristics that deviate from those of a subjectively prototypical human being. The disease–avoidant processes that characterize the behavioral immune system have been shown to contribute to prejudices against obese individuals, elderly individuals, and people with physical disfigurements or disabilities.That a person or group who understands this principle and has access to mass media might choose to exploit this ingrained response mechanism for cynical and self serving purposes is not a novel observation. Specifically, by effectively defining political opponents in the public mind as carriers of disease (socialism, negritude, otherness) a Machiavellian operator can gain varying degrees of control over society (Hitler, Mussolini, Stalin, a long string of former middle eastern gentlemen now residing either in jail, in exile or in their graves, etc.) to restate the obvious.
In addition, the behavioral immune system appears to contribute to xenophobia and ethnocentrism. One implication is that these prejudices tend to be exaggerated under conditions in which people feel especially vulnerable to the potential transmission of infectious diseases.
Additional lines of research on the behavioral immune system have shown that people engage in more reticent and conservative forms of behavior under conditions in which they feel more vulnerable to disease transmission. For instance, when the potential threat of disease is made salient, people tend to be less extraverted or sociable. Evidence suggests that the behavioral immune system also incorporates mechanisms designed to search out and process (heuristic) signs of disease at the level of basic visual attention.
Our Princes understand that "Politics is the continuation of War by other means", they have read and understand Machiavelli, Sun Tzu and Carl von Klausewitz, and the reptilian brain and they form their decisions on those bases. If we understand that we can be the Jackie Chan to their Kareem Abdul Jabbar. Swing voters are by definition 'swingable' and to some degree are so because they smell the disease but are not sure which direction the stench is coming from. The true sources of social corruption are the cynical self serving tactics and those who use them to define certain ideas and groups as virtual Plague Rats.
If this is a reasonably accurate model our current political situation then, to paraphrase Sun Tzu "the wise General will use his enemy's greatest strength against him". I think current as well as historical developments clearly show that this job is made far easier than it might otherwise by the Princes' own words and deeds. Metaphorically speaking, the task at hand for we Peasants is not to build the gallows and tie the rope, but just to keep sawing away at the legs of the stool they're standing on having tied the rope around their own necks.
The problem with their approach is that it always becomes a kind of inverse psychological pyramid scheme where favor in The Court of the Princes inevitably contracts over time because the Princes can only maintain control over their equally cynical second tier followers by pitting them against each other. Many will be watching forthcoming developments in the Empire of NewCorp with great interest, knitting the Phrygian Cap, to see how much loyalty there is among the ever-so-clever Princelings when they are looking at the inside rather than the outside of the Bastille/Tower of London.