From an emotional standpoint, attacking character rather than policies can be a one-way street.

More than ever in the age of social media, when political opponents compete they focus on each other’s character flaws, missteps, and past bad behavior rather than differentiated policy proposals. Some call it the politics of denunciation, and at this point in the evolution of culture, denunciation often focuses on transgressions against identity: perceived racism, sexism, homophobia, islamophobia, or insensitivity to immigrants.

Getting millions of people talking and tweeting about a serious policy proposal is nigh unto impossible, and even when they do, they are likely to hold their opinions with some degree of uncertainty. By contrast, denunciation can be a highly effective political tool because it elicits clear, strong emotional reactions like anger, disgust and righteous indignation, which make it viral. By triggering a visceral, moral reaction, it shapes loyalties and loathing in a…