Caring and being proud of your country is called Patriotism. Worshiping your country/race to the point where it becomes God and you want to deport/exterminate people who are slightly culturally different regardless if they contribute or hurt your country is what nationalism has come to be generally.
nazi = nationalist socialism
Caring and being proud of your country is called Patriotism. Caring about your country and wanting its violent, hateful, subversive, untrustworthy and unhelpful waste-of-benefits Gimmiegrants and illegal aliens to fuck off is a part of Patriotism.
Would you let two hobos into your house? How about five? What if some of them are drug addicts, what if some of them shit on your stairs, what if you end up with twenty seven hobos living in your house, eating your food and draining your money, and only one hobo even bothers to do chores, and even then, all he does is help dry the dishes after you wash them?
"Gimmiegrants should fuck off" is not extremist, and "Gimmiegrants should fuck off home" is not calling for extermination.
"Gas the jews, race war now", THAT is extremist. And I think you've noticed it's only anonymous people on /pol/ who call for race wars against religions (seriously am i taking crazy pills or is everyone else taking them). Fuck those guys, and fuck anyone who tries to paint the entire alt-right as full of those guys. If you say "Pokemon fans, transgender people, and Batman fans are as bad as Nazis", you're going to piss off Pokemon fans, transgender people, Batman fans, and Nazis. It's the same deal here when liberals yelled "All white people are inherently racist" for sixty years.
As for the whole "Cultural differences thing", I'm starting to suspect you don't really get this topic.
It's ok for foreigners to celebrate their own holidays in my country. It's not ok for them to say I can't celebrate my holidays in my own country. And if Vegans were the ones committing a large majority of the rapes and aggravated assaults and crimes in general despite being a minority of the overall population, while committing acts of terrorism against me and my cops and my country and while calling me the evil white meat-eating Nazi who's inherently a Nazi because he eats meat sometimes, I'd be sick of their shit.