Rightwing extremism in the United States can be broadly divided into those groups, movements, and adherents that are primarily hate-oriented (based on hatred of particular religious, racial or ethnic groups), and those that are mainly antigovernment, rejecting federal authority in favor of state or local authority, or rejecting government authority entirely. It may include groups and individuals that are dedicated to a single issue, such as opposition to abortion or immigration.
Rejecting federal authority in favor of state authority? You mean federalism?
Furthermore, how just is it to lump hate groups in with those of the political right? Racism existed long before the Republican and Democratic parties, and it’s existed in both parties since.
For more on this, check out Michelle Malkin’s blog.