Warning! This page contains references to nasty language. Continue only if you're sure you can cope!
What is offensive language?
Obviously the term is entirely subjective. As a culture, we have a general agreement of which words are "swear" words and which words are acceptable. Whether or not swear words are "offensive" is an individual judgment, as it is only the individual who can be offended.
I'm not personally offended by such words as "f**k" and nor are most people I deal with. "S**t" is so common that it barely counts as a swear word. I also don't mind "c**t" but I've found that this word is far less popular. Therefore I use the "c" word very sparingly and judiciously (I don't think I'll ever use it with my in-laws, for example).
In fact, there is nothing inherently offensive about any word. Words are, after all, merely combinations of sounds. What makes them offensive is the meaning, or interpretation, given to those words by the individual. It is the very act of declaring a word to be offensive which makes it offensive.
Desensitisation changes that to some extent. I think the "c" has more impact than the "f" or "s" words solely because it is used less often. Films haven't adopted it, we don't hear it much on TV, so it still retains much of it's special power.
Interestingly, despite the weakening of many old favourite swear words, I don't see any new high-impact cusses taking their place. F**k and c**t are still considered to be pretty much as bad as it gets, but they are losing potency.
I think we can take advantage of this situation.
I wonder what would happen if we decided one day that no words were offensive. If no-one minded being called an arsehole, then the word would lose it's impact, and would no longer be an insult.
One could argue that the best way to eradicate all offensive language is to stop being offended by it.
The challenge then becomes encouraging people to use the language more effectively rather than less badly (sic).