either through law, or through social custom, against being offended. Free speech is free speech, and not only when it does not offend someone.
We can't have it both ways! We can't pass laws to protect anyones sensitivities for either side.
Look at how the current Regime tries to make laws forbidding people to wear clothing which carries messages opposing the war and opposing the Bush Regime. We raise all kinds of hell (and rightfully so) against such high-handed actions, yet some on our side want to prohibit the morans on the other side from spreading their messages.
Perhaps it IS a damn shame, but there it is!