The work of cartoonist Thomas Nast helped expose the corruption of Boss Tweed's Tammany Hall. Lenny Bruce's provocative jokes about race made him a hero for free speech activists and challenged our prejudices.
As Arianna Huffington wrote, "political satire at its keenest has always been about speaking truth to power."
The question is, when does the jab...hit below the belt?
Some people say Wanda Sykes went too far at the White House Correspondents Dinner, joking that Obama foe Rush Limbaugh was supposed to be the 20th hijacker on 9/11 but was so strung out on oxycontin he missed his flight. She also wished him kidney failure.
Rush Limbaugh has delivered a barbed zinger or two, and some are saying turnabout is fair play.
Humor is great in most situations, but good natured ribbing can devolve into just plain nastiness … producing a lot more heat than light.