That was pretty bad, and I hope it isn't a window into the quality of thinking at DHS. Sloppy specialized technical language will lead to mistakes and poor judgment...so I fear the worst.

I'll bet this definition was a little unsatisfying, eh?

(U) rightwing extremism
(U//FOUO) A movement of rightwing groups or individuals who can be broadly divided into those who are primarily hate-oriented, and those who are mainly antigovernment and reject federal authority in favor of state or local authority. This term also may refer to rightwing extremist movements that are dedicated to a single issue, such as opposition to abortion or immigration.
(also known as far right, extreme right)

Well yes, of course the "extreme right" is on a list of domestic extremists, being extreme and all.

The flat glossary format exacerbates the problems. This is the sort of thing that cries out for a taxonomy that, first, defines fundamental terms like "rightwing" and "extremist" (yes, it is possible to insert a space between those two words) before plummeting into detailed descriptions of individual groups.

I'll go looking later when I have time, but by any chance do you know of such a taxonomy? I've seen philosophical taxonomies that arrange classical schools of thought, and there's some overlap with this list, but I'd like to see a taxonomy that makes sense of the DHS's view of "domestic extremism". Or, probably better, a broader taxonomy of modern domestic political groups, because "extremism" is a matter of where you're standing in the taxonomy.