Roughly half. The point is still valid and it's important not to disregard the momentum of that segment of the country
This is naked white supremacism. For as much bullshit as we've heard about political correctness, why not just come out and say this is straight up religious and racial discrimination?
The president's Chief Strategist and Senior Counselor is a white nationalist, who used to run Breitbart.com, where there is a distinction made between white supremacists and white nationalists (I cannot explain the distinction, for I don't see one). A site all about how awful multiculturalism is, separation of races is necessary for the survival of a country, etc.
Without letting down your guard or concern, my advice is to moderate it with another possibility. The U.S. has much better insulation geographically than European countries, and a history that involves worse rhetoric and divisiveness and we've survived. There might be a pro where the whole world sees what even a little bit of white nationalism does to a country, and all those European countries flirting with their own far right nationalists, and have elections coming up soon, might just have an "OH FUCK NO" moment.
And that's probably better than if Europe were electing far right governments before the U.S. Europe has a history of conflagration. Maybe Europe gets cold feet and starts taking far right nationalist politics more seriously, and rejects it more concisely and clearly, at election time. It's much easier, safer, more stable, to squash this at an election.