> Is there some special property of the US that makes it immoral to control its territory like other nations?

Whether or not other people/nations do something is not a good arbiter of morality. But that aside, most other countries didn't just impose a large-scale immigration ban like the US just did.

No, all the other nations have that property as well.

He's pointing out the contradiction people hold in their heads, not saying that it's immoral. Many people believe in mutually incompatible ideas like this. I think it's because they get more satisfaction from fitting in with the crowd or experiencing the pleasure of reinforcing their beliefs than they do from trying to be right, which is emotionally unrewarding.

I think they should be honest and say "It's OK to discriminate against people based on the circumstances of their birth but I make an exception for race because my society told me I must." It sounds kind of stupid, but it is stupid. That's the cost of honesty.