Welcome to the internet. By it's very nature, it's a public forum. By joining it, you've agreed in principal to having your postings here seen by people all over the world. If you are afraid to stand by your comments, don't post, or, much better in my opinion, think about what you're writing. All speech (writing, talking, internet posts, etc.) has effects and consequences, some you might realize, others unknown and sometimes unintended.
People today seem to forget that. It might help to remember that the American Revolution was fought not only with guns, fighting and speeches to gatherings, but also, more effectively, by the writings of the people instigating independence. Payne, Franklin, Jefferson, Adams, Revere, and many others wrote constantly about the reasons and need for revolt long before the first shot was fired. Words, especially printed (yes, internet posting is a form of print) have power long after the smoke of battles have cleared or the author or speaker have gone.
This is also the reason people like Glen Beck, Rush Limbaugh, certain politicians, and others should be held partially responsible for the violence that occurred when the Health Reform Bill passed. Having a difference of opinion is fine, saying that property damage should be done, people should be threatened with physical violence for voting a certain way, saying that elected representatives should be made to be 'afraid to step outside their door', and advocating secession are irresponsible and dangerous statements to make over the airwaves and in public speeches if you are not ready to see their actuality.
It's akin to yelling 'FIRE' in a crowded room and claiming 'free speech' and 'I didn't know that people would stampede for the exits. It was just a joke.' Want to try making a joke around TSA folks about hijacks and bombs? Try claiming 'free speech' as you get hauled to an interrogation room for a couple of hours while the [sic] do a full background check on you.
Oh, yeah...you have heard about employers searching the social sites for info about prospective (and possibly current) employees, haven't you? Again, the net ain't a private club, it's a public soapbox in the middle of a large square in a big city.
If you don't care to own your own comments, or have others see them, why make them in a public area?
just my 2 cents and another ramble....sorry if I bored ; )