Which is why some of them are threatening the creators of South Park with the "Theo Van Gogh" treatment, for airing an episode that mocks the "Prophet" Mohammed.
Humorless societies, those that aren't able to understand, tolerate or accommodate an alternate point of view, are ultimately Dead Societies. They become static, bureaucratic and all the human ingenuity is slowly, but inexorably, strangled from them. The Muslim World is in a death spiral right at this moment, and doesn't even realize it. It's defiance is the aggression of those for whom there is no hope.
Primarily, it can't recognize it's own eventual demise because it is currently propped up by Western dependence upon Middle Eastern oil, so that Muslim society can at least continue to buy the extraneous impedimenta of modern civilization (electronics, medicine, weapons, machinery, and so forth), and what passes for government in many Muslim lands can still enjoy some sort of aid and support from Western governments. Where oil wealth does not support the population, the need for unskilled and cheap labor in the West encourages Muslim immigration, and then those immigrants manage to eventually to take advantage of the generous welfare systems available in Europe and the United States to support themeselves and their families, without actually contributing to their adopted society, or assimilating. Their own culture produces very little of worth, and even less that will sustain it, should the West a) ever achieve true energy Independence, or b) go extinct tomorrow.
Islam cannot create. It can only control and destroy. Creation requires the ability to ask the fundamental question: "Why?". Islam cannot tolerate "Why?", because to ask it is to begin a journey which always ends with the individual questioning God ... and Her motives. The question of "Why?" has already been answered by God, through Mohammed and his stupid book, and cannot ever be asked again. Curiosity kills in Islam. Without curiosity, there can be no progress and no life.
Left to their own devices and assuming the rest of the human race disappeared tomorrow, Muslims would eventually inhabit a world that has no creativity or dynamism. It would be the Arabian Desert writ large, in all senses; there would be no Art, no Science, no intellectual pursuits, that wouldn't be subject to the control of the Imams and the Dictators they anoint. It would be a society which existed solely to repeat the useless devotions demanded by a system of thought control disguised as a religion, and within a very short span of time, millions would die from preventable diseases, starvation, internal strife, and the lack of progress.
In this regard, anything a Muslim has to say on any subject is suspect, indeed laughable, in my book. They're a dying and mentally-arrested breed, and thus, of no accord.
However, even the dumbest of dogs manages to bite the mailman every so often, and so the South Park guys should take the threats they've received seriously. These are people for whom murder is excusable, in fact, it's a requirement in their religion, so beware.
But, the incident serves as yet another example of why Islam is doomed; any system which is absorbed by questions of whether it's okay to kill and eat a goat you've screwed, which believes earthquakes are caused by short skirts, where music is considered the gateway drug to promiscuity, which is so absolutely obsessed with it sex that it has made it a crime punishable by death, a society which has no sense of proportion or sense of humor, is a society too stupid to survive.
If Matt Stone and Trey Parker would hope to survive, I would suggest a retinue of bodyguards. Some of these Muslims are apt to become unhinged and violent when you poke fun at their child-molesting prophet.
Its about time we stopped believing in the "transformability" of the Muslim world, and started taking seriously our War on Terror. To date, all the drone-fired missiles and bombing-with-sensitivity doesn't seem to be working; there's still a supply of idiots willing to murder and intimidate those they don't agree with, and laboring under the misapprehension that Heaven awaits them if they do.