Many of the individuals charged in the January 6, 2021, attack on the U.S. Capitol did not have ties to far-right extremist groups, leading some pundits and researchers to speculate that extremism has become mainstream and much more common in the current political environment. In this article, we discuss events before and during January 6 that affected extremism and pushed people toward polarization. Specifically, we discuss the role of the media, especially social media, in developing like-minded content sharing and polarizing, extremist group norms. The role of groups to drive people toward protest is discussed within research on social movements. The role of identity and acceptability of prejudice toward outgroup political members and how this identity fed into increasing extremist rhetoric are also discussed. Then, we discuss conditions of the day of January 6, including establishment of norms through rhetoric and the social proof of extremist action, and also, the easy exit of those who could leave an increasingly escalating situation. Finally, we address the implications for the current political climate, including the potential for increased violence and extremism. Highlights and Implications• This article seeks to answer the question: What drove people normally not associated with far-right extremists to take part in the January 6 attack on the U.S. Capitol?• This article highlights the role of social media in creating homogeneous networks, where ideologically like-minded individuals shared emotions, concerns, and grievances.• The role of identity and affective polarization in driving outgroup animosity and affectively polarizing rhetoric is discussed.• Events during January 6 that contributed to violence include polarizing rhetoric, easy exit for dissenters, escalating social proof, and development of more extreme norms.• Implications of increasing political violence are discussed, as the events of January 6 have further polarized the public in the United States.