Can you tell me your definition? I could be wrong.
There's a little more to it than just nationalism in a predominantly white country, though. Nationalism generally means support of national identity above all else. This article promotes white identity above national identity, but the outlet for that feeling is to make the nation into a white nation, so that supporting white culture and supporting the nation are one and the same. Note that the article never talks about American culture. It talks about white culture and white identity politics.
I'm trying very hard not to criticize anything in these comments. I'm really just trying to summarize the description that article provides. It's not like I'm uncovering a hidden subtext, I think the authors would generally agree with my summary.
I'm not using white nationalist as an insult, I'm calling Breitbart white nationalist because that accurately describes the beliefs that they cater to. Maybe Steve Bannon wouldn't call himself that because it's obviously a politically and emotionally charged term, but if he agrees with the views described in this article, he is a white nationalist.
There's a little more to it than just nationalism in a predominantly white country, though. Nationalism generally means support of national identity above all else. This article promotes white identity above national identity, but the outlet for that feeling is to make the nation into a white nation, so that supporting white culture and supporting the nation are one and the same. Note that the article never talks about American culture. It talks about white culture and white identity politics.