I'm half Scot half Swedish and born in Scotland but bought up in London.
I've only ever had the mickey taken out of me about the Scottish part and never about the Swedish part.
I'd like to complain that I've never had a single racist comment made to me about the Swedish part of my ancestry even though Abba come from the same land.
Seriously though, maybe history plays a part in what is racism and what isn't.
Also, culture plays a part as well. In the UK we all have a similar culture so calling a Scot a 'sweaty sock who is very mean' means, in terms of racism, something very different to an isolated comment about 'Asians are expert at making claims'.