Paul1977:
That's just not true though. Language changes and evolves. In the 50s, 60s, and 70s "Negro" was considered an acceptable term by both black and white people. In fact, the term "black" was initially considered offensive by a lot of black people - but now it is the preferred term in the USA.
EDIT: Ignorance doesn't necessarily equate to racism. It is perfectly possible to offend, without having any intent to offend. Intent is important.
Intent is irrelevant it is the effect on the target person or persons that takes precedent. Also ignorance does not mitigate or justify racism. It is the effect on the target person or persons.