Over the past few years, far-right nationalist political leaders around the world have been using harsh rhetoric against minority groups, particularly immigrants. We know from history that acts of genocide, ethnic cleansing and terrorism have been preceded by periods in which political and social movements employed such rhetoric. In Nazi Germany, Jews were described as vermin, and Nazi propaganda outlets claimed that Jews spread diseases. The recent ethnic cleansing of the Rohingya people of Myanmar was preceded by propaganda associating Rohingya men with rape.

In the United States, we had the “superpredator” theory. Violent-crime rates in the country started dropping in 1993 and continued dropping throughout the decade. And yet, in 1996, criminologists began spreading an unjustified panic about so-called superpredators — “hardened, remorseless juveniles,” according to the political scientist John DiIulio — that led to a wave of new state laws with harsh sentences for minors. Politicians’ descriptions of young black men as “thugs” and “gang members” in the 1990s helped transform the United States into the country with the world’s highest incarceration rate. Black Americans constitute 40 percent of the incarcerated population while representing only 13 percent of United States residents.

Power over an individual is the ability to change someone else’s behavior or thoughts in accord with one’s desires. One way to control someone’s behavior is through force. A much better way to change others’ behavior is by possessing the capacity to change their obligations. If you can convince someone that they ought to do what you want them to do, your power is genuine authority. But do words really have power to change our behavior?