The KKK may be considered an almost-there terror organization, but it is not officially one. Also, I'd reckon membership would drop like a brick if it does get classified as a terror organization.
These groups tend to be paranoid and often have an anti-Democrat thing. Classing them as a terrorist organization might actually play into their "the libruhls is out to get us" rhetoric.
FTFY. These groups tend to have a much lower profile and be less prone to batshit craziness when a Republican administration is in office. All those militia groups and white supremacists from the 90s got a lot quieter once Dubya was in charge. And then promptly revved up the crazy machine once a n----r (gasp!) was in charge. (Though to be fair, they started revving it up in the last two years of G-Dub's tenure because he was seen as too liberal and a lame duck.)
The real test would be to see their reaction to a black Republican president.
In the wake of the Michael Brown/Eric Garner/every-other black-man-shot-by-cops furor, and the backlash against that furor, it's going to be interesting to see how this plays into the 2016 campaigns.
Which candidates on the right are going to dog-whistle the hardest to get those juicy racist votes, (which are by no means confined to the Southern states)?
Which candidates on the left are going to court Al Sharpton and the anti-police demographic?
Which candidates on the libertarian right are going to shoot for a crossover by calling for law enforcement reform? (
Rand Paul is already dipping into that well.)