In the past, extremist ideologies and movements have existed on the fringe of mainstream society. Today, domestic violent extremism has found a new home and greater acceptance as technology provides the means to connect disparate communities across the country. Domestic violent extremists seek to undermine our democratically elected government, threaten the peaceful democratic processes, and deny many Americans their civil rights and liberties. To appropriately respond to the threat of domestic extremism, it is critical first to understand the root causes and cultural landscape that have allowed extremist ideas and groups to gain a foothold in American society.