On the other side of the spectrum, you see someone like Donald Trump, who is using as the basis of his campaign political incorrectness. It's clearly intentional. He'd have to be a complete moron just to coincidentally insult Mexicans, and women, and disabled people, and Muslims. So clearly he's using it as a vote winner. But I think with comedians there's a responsibility.
I think you can be politically incorrect, but there's some responsibility with that. You've got to make sure that you are not condoning or bolstering any racial or other stereotypes. You've got to be free to make jokes, but just make sure...you don't want to go and black face somewhere to just prove a point. If it's insulting and offensive just for the sake of it that's problematic.
I remember, when I was in university I studied history, and there was this one major historian of the Third Reich, Ian Kershaw. And his quote was, 'The path to Auschwitz was paved with indifference.' I know it's not very funny being a comedian talking about the Holocaust, but I think it's an interesting idea that not everyone in Germany had to be a raving anti-Semite. They just had to be apathetic.