The U.S. faces a growing threat of domestic extremism, embodied by the Jan. 6 attack on the U.S. Capitol. We wanted to know what it actually means to be an extremist. Is a certain type of person drawn to extremism? What convinces someone to join an extremist group? And how might our own friends or neighbors go down that path? Rachel Nielsen is the director of the Colorado Resilience Collaborative, which focuses on combating violent extremism. She sheds some light on these questions and more.