When does it become offensive?

A satiric cartoon that has gained a lot of attention over the past few years is this cartoon portraying the president of South Africa, Jacob Zuma, when he is about to rape the Justice system. In a documentary that is currently showing here in Sweden Zapiro, the creator of this cartoon, explains why he decided to create the cartoon. He states that for him it is natural to be an activist and a satirist at the same time and that the cartoon was his statement against the power abuse and corruption of the South African government. In the documentary, he also enhances the power of satire by stating that his cartoons are often used in English and history tests in South Africa.

Since Zapiro was an active satiric cartoonist during the apartheid period in South Africa, he says that it is natural for him to protect democracy. He also says that he is probably willing to go further in doing this than most other people, which brings me to the title of this blog post: How far can you go with your satire, when does it become offensive? Personally, I think that Zapiro had every right to draw Jacob Zuma like he did. What I sometimes have trouble with are satiric cartoons of Mohammed. What do you think? Can everything be satirized and, if not, where do you draw the line?