That's a inference that you're making, without any proof that's actually want all "white nationalists" endorse. Did you read the article from The Nation describing black nationalism? It actually accused "the Establishment" and the right of misrepresenting that black nationalism was inherently violent.
Again, if you take a platform of excluding immigrants, whites voluntarily choosing not to associate with black people, and couple that with reducing all welfare benefits (under the belief that this would cripple black people), you have a "white nationalist" agenda that requires no violence, and without whites being legally privileged.
It's odious, racist,and un-American. But it doesn't have to be endorsing violence.