This is a rather insidious term used mostly to limit the free speech of those who think 'differently.' Free speech, as defined in the 1st amendment (see below) of the US constitution and in the eyes of our founding fathers, really means FREE SPEECH.
"Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances." -1st Amendment
Note that it does not say
congress shall make no law EXCEPT WHEN.... This is important because there are societal forces at work seeking to limit one of our most fundamental rights and undermine our constitution. These forces have managed to get a foothold in Canada, Europe and India.. through "hate-speech" laws, and through explicit exemptions in their constitutions which permit limits of speech in the "greater interest of the nation" etc. These exemptions do not exist in the US constitution, and for good reason. Our founders realized that the best way to prevent tyranny and oppression is not to have so called
enlightened bureaucrats and politicians determine who can say what, and when.. that the freedom of the individual is always to be held higher than the so called "greater interest" of society. You can see a great argument for Absolute freedom of speech in the video here:(
http://video.google.com/videoplay?docid=6379618149058958603&ei=SZhOSuKxNIzyqgO6j4DEBg&q=hitchens+free+speech)
Recently, a friend of mine was lambasted by someone who was "offended" by an argument he made regarding terrorism and Pakistan (
http://arg.umentum.com/arguers/GauravBhatia?show=terrorists_have_no_religion). It was claimed by the offended party that there are "educated" people dedicated to pursuing this debate, and his intrusion into their territory was unacceptable. This sort of sentiment must be fought at every level, since its aim is to ultimately prevent people like you and me from speaking their mind.