One of the first scenes in the ridiculous but thoroughly nasty film Innocence of Muslims shows angry Muslims running through the streets smashing things and killing people. So what happens when a clip dubbed into Arabic goes up on the internet? Angry Muslims run through the streets smashing things and killing people.
It's as simple as that: Press the right button, and they'll do what you want. Some Christian extremists set out to provoke Muslim extremists into violence that would discredit Islam in the eyes of the West - and it worked. As the US consulate in Benghazi burned and the American dead were carried out, many people in the West thought to themselves: "The Libyans are biting the hand that freed them".
Maybe the Christian extremists don't understand that their film serves those who want to overthrow the moderate, democratically elected governments, both Islamic and secular, that have come to power in the "Arab spring". Or maybe they do and hope the violence they are stirring up will bring Muslim extremists to power in those countries. After all, it's easier to mobilise Western opinion against fanatics.
The leaders of the Arab world's post-revolutionary governments have to walk a fine line, denouncing both the film and the violent protests. Moderate Islamic governments like that of Egypt's Mohamed Morsi have a particularly tricky task, since they are competing with the Muslim extremists who are organising the protests for the support of the same pious and socially conservative voters.
"We Egyptians reject any kind of assault or insult against our prophet," Morsi said, "but at the same time we firmly say that this cannot be taken as a justification to assault consulates or embassies and cannot be taken also as a justification for killing innocent people."