When hateful rhetoric spreads, whether online or offline, its damage extends far beyond the direct victims. We find that hate speech fundamentally threatens the bedrock of society—community cohesion. It actively works to fracture social relationships, erode shared democratic values, and deepen existing societal divisions, making it one of the most common ways of spreading divisive rhetoric on a global scale. This is why international bodies, including the United Nations and UNESCO, view the fight against hate speech as critical to advancing peace, human rights, and sustainable development.

Widespread exposure to hate speech, even among those who are not the direct targets, diminishes overall levels of trust and fosters a climate of fear and trepidation. Witnessing or being secondarily exposed to hate crime or hate speech in a neighborhood or community setting can significantly increase an individual’s perception of threat. This sense of danger is linked to increased feelings of vulnerability and leads to the anticipation of social rejection, making people more reluctant to engage with neighbors perceived as different from themselves. We see that this creates stronger bonds within the targeted social group (an internal defense) while simultaneously erecting barriers between groups in the broader community.

Why does this happen? Widespread hateful content, particularly online, serves as a social indicator. Studies show that when individuals are repeatedly exposed to hateful comments, they estimate the share of the general public holding negative attitudes toward the attacked group to be much higher. This effect, which can increase polarization, makes people believe that their society is more prejudiced and less cohesive than it might actually be. We know that online environments amplify this effect, as platform designs reward emotionally charged, extreme content with greater engagement and visibility, quickly spreading divisive rhetoric and strengthening online echo chambers where unchallenged, extreme views proliferate.

What is the result for society? We see that hate speech actively undermines inclusion, diversity, and the feeling of belonging. It fosters an environment where victims feel marginalized and may withdraw socially. Witnessing hate can also lead bystanders to develop negative beliefs about the targeted groups and to take actions aimed at exclusion, such as being reluctant to move into diverse neighborhoods. We see that counteracting this effect requires systemic, concerted efforts—not just online content moderation, but also offline actions aimed at rebuilding fragmented communities and facilitating meaningful interactions, such as promoting ethnic and religious mixing in educational settings.