And many Christian churches prominently display art featuring Satan. It's always less about what is actually in the picture and more about the message the picture is supposed to send and how people actually interpret it.

Hitler and Nazis have been used as comic reliefs in Western popular culture. You can supposedly make anything more funny in an absurd way by adding some gratuitous Nazis. Communist leaders such as Stalin and Mao are often used ironically. Sometimes because people find the socialist realism art style aesthetically pleasing, and sometimes due to the irony of turning a communist leader into commercial art.