Oh surely, it was, to begin with a way for slaves to put each other down. But we forget that back then, they were slaves, we're just the progeny of people who were slaves, then second-rate citizens, and then simply an impoverished (in more ways than one) minority. We're down the timeline and only know, by historians what it means (and apparently many people don't know that it was used as a way to refer to—nay, describe the Africans, before it was used in a derogatory way). Now the meaning is different, again. The connotation is different. There are plenty of words like this. I already mentioned “fag” but think about it deeply. Where did it come from? A Faggot, which originally meant a bundle of wood for burning. Apparently in antiquity they wrapped up homosexuals with kindling and burned them, probably a lot like witches were burned at the stake. Sometimes it's used derogatorily and sometimes as a term of endearment or a friendly chaff or even a jab.
Words have as much power as human intention gives it. Thats why it's always context which must be considered, and even then... some people will say things they don't mean, sometimes.
Here are some other words, kinda like that, ranging from insensitive to downright offensive in some connotations
Canuck – an insensitive way to refer to a Canadian, but is also one of their Hockey teams (Vancouver)
Cabron – a term that has lots of (vulgar, insensitive, disgusting) meanings, but is also used casually by men of Latin descent to refer to each other--
Fag, -got – need I say more?
Dyke – even the Wiki for it says “it has to some extent, been reappropriated”
JAP – No, not that one, Jewish American Princess
Jew – yes, Jew. Ironically.
Native American – it offends some, and yet others may refer to themselves as this, as well as:
Indian – what a foible, Christopher Columbus made...jeez.
Packie – a Packistani
Gypsy – some say it was started due to the predessecors of modern day nomadic Romani being directly from Egypt (They were referred to as “Egyptsies”, apparently), but now its actually considered a slur to many. However, some would use it casually.