In 2006 when I was making Lotus's acquaintance, leftist extremists were known as moonbats and righty extremists were known as wingnuts. Both terms were used freely on the old Yahoo boards without the need for further clarification. Here's a NYT article from Sept 2006.Quote from: "Peaches"
I'm not saying the terms are carved in stone, only that those usages still work for me and I still use the terms in the same way.
There's also a quick scan of the first page of Google hits for "urban dictionary wingnut" ...
Wingnut has been in use here for decades... used on a non Asian person, it just means crazy... used on an Asian, it's a racial putdown...