I have not read his manifest but have seen a few quotes from it: he might have shared some ideas with the rightwing, but he also seem to live in his own world and have some pretty weird ideas not many on the rightwing would agree with IMO.
Do people consider Lee Harvey Oswald a leftwing/communist terrorist or assassin or simply a deranged person? Should anyone who dislikes capitalism feel guilty about Rote Armee Fraktion?
I don't know what you mean by "rightwing" but unless you can find a group that advocate for what ABB is rambling about as well as his actions, then he is still just one single madman. Fascists and Nazis come closest I guess?
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