Sorry- It is an opinion piece, you're right I shouldn't be quoting it as reporting.
My Apologies.
I don't think the writer is trying to say that all conservatives are white nationalists, but that white nationalists will gravitate towards conservative parties. I think he is trying to say that: Not most conservatives are white nationalists, but most white nationalists are conservatives.
I think there are a lot of conservatives who think like you do- wanting to purge your party of this scum, and I applaud you for it.