A good discussion on NPR about political cartoons and violence —
Do Editorial Cartoonists Draw the Line?
Talk of the Nation, February 9, 2006 · The visceral — and in some cases violent — reaction in the Muslim world to Danish cartoons of the prophet Muhammad have raised all sort of questions about the freedom of speech and cultural sensitivity in a globalized world. It also reminds us of the power of the political cartoon.
Neal Conan talks to cartoonists Mike Luckovich of the Atlanta Journal Constitution and Ann Telnaes, whose work has appeared in many newspapers, including The New York Times and The Washington Post, about their craft. Joining the discussion is Stephen Hess, co-author of the book Drawn & Quartered: The History of American Political Cartoons.
Here's a link to the NPR site (and more cartoons), from which you can click to listen to the interview.