Good questions, Bad Wolf. The first is white supremacism, the other is nativism or nationalism.
White supremacism is bad, i.e. hating black people simply for being black. Other forms of supremacism are also bad. ISIS are Islamic supremacists, hating and killing the other. The WTS are also supremacists. Think about it: their belief is that their religion is the only true one and their God will kill all non-JWs soon.
The other, nativism, is entirely proper. I'm white and I live in the UK, a white-majority country.
And I want it to stay that way. Before any SJWs start howling 'racist!' and reach for the smelling salts, no I'm not actually racist. I don't hate the Black-, Chinese-, Indian-British people already here. Although I'd say there are issues with integration, most people from the ethnic minorities are integrated fairly well and speak good English.
And if I met, say, a nice Black girl and we clicked, I'd date her/start a relationship/marry her. In fact, I did actually meet a nice Black girl at uni. She had a nice, friendly personality and curves to die for. We met up a few times and went out on a few dinner dates. Nothing came of it because I wanted to focus on my studies - I hadn't moved 200 miles north to fall in love or get laid. But I'm glad I met her and knew her for a while.
However, I don't want whites to become a minority in their own country.
It isn't just whites who are like this. When African countries gained independence, Francophone countries such as Zaire shouted "Afrique aux Africains!" - Africa for the Africans! And by 'Africans' I don't think they meant white people.
And then there's Japan. The main ethnicity and culture are the Yamato people's. And Japan wants to keep it that way. A hate crime? No. Supremacist? No. Discriminatory? No, as long as immigrants integrate, accept the dominance of Japanese (Yamato) culture, and learn the Japanese language (Nihongo).
The word 'racist' has been said so often and misapplied that it has lost all meaning. So, some trendy people are starting to use 'nativist' as a similar label and way of shutting down debate. I've seen it in the Guardian a few times. But I doubt it'll catch on - virtually every group of people are 'nativist' and it is entirely proper.