Aussies have that shit on lockdown. Was talking to a couple of Yanks who were in the navy (I think) when we were in Hawaii and they were shocked to hear us say that (I was with a Kiwi, an Aussie and Mrs Hun who is Northern Irish), but then they went on about how douchebag is super offensive and I just laughed.
Cunt is my preferred slur to yell out the window of my car. Never found a word that offends more people (men and women). Although it doesn’t elicit an immediate punch to the head like nigger does.