Over at Reason, the discussion of Geert Wilders' movie took an interesting turn when a commenter named Paul brought up this notorious T-shirt. While I'm no fan of Christianity, the cult of Christ is relatively harmless these days. The following choice boils down the difference between Christianity and Islam pretty well.
I spent some time thinking about it. Really thinking about it. Then, I imagined a scenario. Two T-shirts — pretend you have to wear one of them, publicly. One says "Jesus is a cunt", the other says "Muhammed is a cunt". Which one do you wear?
I think Paul's meaning is, "Which one do you wear without fear of violent repercussions?" And that, alas, is a no-brainer.