Calling banjo music "nigger tunes" was always racist

Well, no. It was actually another of your expressions, completely "normal". Through my banjo-playing friend referred to somewhere above, I have come across musicians of whatever hue who refer to these tunes thus because this is how they are classified musically. A verbal shorthand, if you like.

In one of those interminable war films there was a dog called "Nigger". Because he was black. I understand that the word is now dubbed over. Once there was a fabric dye called "Nigger Brown" which described exactly what it was on the actual tin but you can no longer get it.

This all seems rather trivial when confronted with real racism, and the actual threat to our cultural heritage from the nasty right.