 In the June 2006 edition of Harper 's Magazine Spiegelman had an article published on the Jyllands @-@ Posten Muhammad cartoons controversy ; some interpretations of Islamic law prohibit the depiction of Muhammad . The Canadian chain of booksellers Indigo refused to sell the issue . Called " Drawing Blood : Outrageous Cartoons and the Art of Outrage " , the article surveyed the sometimes dire effect political cartooning has for its creators , ranging from Honoré Daumier , who spent time in prison for his satirical work ; to George Grosz , who faced exile . To Indigo the article seemed to promote the continuance of racial caricature . An internal memo advised Indigo staff to tell people : " the decision was made based on the fact that the content about to be published has been known to ignite demonstrations around the world . " In response to the cartoons , Iranian president Mahmoud Ahmadinejad called for submissions of antisemitic cartoons . Spiegelman produced a cartoon of a line of prisoners being led to the gas chambers ; one stops to look at the corpses around him and says , " Ha ! Ha ! Ha ! What ’ s really hilarious is that none of this is actually happening ! " 
