he isn’t a right wing nationalist, he is a left wing fascist both can have nationalist beliefs.
At a glance, I'd say the manifesto holds on its face considerable cultural value as a snapshot of the zeitgeist, the spirit of the times, as seen by a small, deeply alienated segment of the populace. The fellow is obviously bright, thoughtful, and in tune with the times, but he's also a nut. You can almost hear the loose screws rattling around in his head. I wouldn't be surprised to learn later that he's got an undiagnosed psychiatric condition. There's a passage in the manifesto you'll know the one I mean if you've scanned the manifesto yourself that makes me suspect bipolar disorder.
In any case, this ugly event isn't going to lead anywhere good. :/