The only time that I experienced genuine dislike for my nationality was when I told a Serbian person at a training that I was giving that I’m American. I think that feelings run deeper when your home has been bombed or invaded or similar by another country.
My father in law has no time for Germans, which I kind of get since he is a Dutch Jew and half of his family was killed during the German occupation of the Netherlands.
I thought that it came from people buying cars from Japan and then modifying them both for more horsepower and to look cool?