For heck's sake, read the whole article. He doesn't explicitly make that distinction, but it's implicit. It's why he keeps saying "the continental right" and "Europes cultural conservatives."
The problem, though, is that there's no impenetrable wall between Europe and the US, especially now with the Internet. This nut took a lot from some US and English-language websites, and Douthat is only being honest in acknowledging that.
Connections are going to be drawn, as they were in the Gore-Unabomber matter and the response has to be more than just a blanket denial. You can certainly disagree with Douthat. His isn't the last or best word on this case. But in a world where people will tell you that a fanatical anti-Muslim is somehow in spite of everything a "Nazi-Muslim", Ross isn't a moron.
Why yes he is, a moron that is.