Civility?

Civility. Now that's a word I haven't heard much until just very recently. Why all of a sudden are we to be civil? Is civility akin to political correctness? Is it yet another way to control our speech? And, just what constitutes civility? Am I uncivil if I disagree with you? Are you uncivil if you disagree with me? Is civility yet another liberal ploy to misdirect the political discourse? And, just who is to be the Civility Police? And, what is the penalty for being uncivil?