(Muhammad Sajjad ~ Associated Press)
This one also is within Islam, and it helps explain the multiple personalities of the fury.
It's political: The uncompromising ethos of extremism clawing for any gains against more moderate voices. It's social: Fed by an explosive blend of economic stagnation, anger over U.S.-led wars and -- in some places -- frustrations as the soaring hopes of the Arab Spring hit the grinding realities of rebuilding.
And it cuts deeply into questions that have added resonance in a hyperconnected world that moves at the quicksilver pace of the web: How to coexist with the free-speech openness of the West and whether violence is ever a valid response.
"Our manner of protesting should reflect sense and reason," urged Egyptian-born cleric Youssef al-Qaradawi in his Friday sermon in Qatar's capital Doha, where he has found a worldwide audience through the web and a show on the pan-Arab network Al-Jazeera.
Yet such appeals -- while frequent from many Islamic leaders and scholars in the past week -- have competed against opposing calls that can tap deeper passions. Political factions and hard-line clerics across the Muslim world have been quick to try to capitalize as after other perceived offenses against the faith.
"There's no doubt that every Muslim feels in some ways deeply troubled by any insults to the Prophet Muhammad, but how many have seen the video of this movie to make up their own minds? Very few," said Sami al-Faraj, director of the Kuwait Center for Strategic Studies. "You need someone to organize the protests and, in effect, throw the switch."
It's come in many forms.
Ultraconservative Islamists have apparently taken the lead in protests in Arab Spring countries such as Tunisia and Egypt attempts in a show of force against the new leadership and their Western allies. In a curious battle of perceptions, Egypt's Muslim Brotherhood-led government called out riot troops to protect the U.S. Embassy against protesters also claiming to "defend" Islam.
In Libya, U.S. investigators are examining whether armed militants used the uproar over the film as cover to launch preplanned attack on the U.S. Consulate in Benghazi, killing the ambassador and three other Americans. The U.S. ambassador to the United Nations, Susan Rice, said Sunday the attack was not coordinated and premeditated, but others have challenged that view.
Crowds in Yemen condemned the film -- but also chanted against the continued U.S. military presence such as drone strikes that have targeted suspected al-Qaida leaders.
"Obviously there's a latent anti-Americanism that is coming out," said Salman Shaikh, director of The Brookings Doha Center in Qatar. "But that is only part of this. This is primarily about a struggle for the soul of these states."
Elsewhere -- from Nigeria to Australia -- hard-line clerics and parties have mobilized demonstrations in both expressions of anger and messages to rivals. In Iran, protesters were given premade placards denouncing the U.S. in a clear sign of a state-organized demonstration.
On Sunday, Iranian newspapers reporting that a religious foundation has increased the reward for killing British author Salman Rushdie to $3.3 million from $2.8 million in response to alleged insults to the Prophet Muhammad in his novel "The Satanic Verses." Iran's late Supreme Leader Ayatollah Ruhollah Khomeini issued a death fatwa against Rushdie in 1989, but Iran officials later distanced themselves from the edict.
Bahrain protest groups, meanwhile, have used Twitter to organize demonstrations the including burning American flags in the nation that hosts the U.S. Navy's 5th Fleet. Pakistan's conservative Islamist parties sent out text messages, mosque announcements and made phone calls to bring out protest crowds, including about 1,000 people in the northwestern city of Peshawar on Sunday.
"What kind of freedom of expression is that which hurts the religious sentiments of others?" said Haider Gul, a grocery store owner who joined the anti-American rally.
This question is not new -- tumbling back over centuries and different faiths. It flared anew in 2005 with a Danish cartoon of the Prophet Muhammad that was deemed offensive by many Muslims, and was a centerpiece of the debates after the 2004 slaying of Dutch filmmaker Theo van Gogh, whose film "Submission" criticized the treatment of Muslim women.
But the current video, "Innocence of Muslims," brings a new element: What if the sole intent was to provoke backlash and violence? It's unlikely to bring any clear-cut answers in the short term. America's free speech protections give a wide berth for the filmmaker, Nakoula Basseley Nakoula, a self-described Coptic Christian whose movie denigrated the Prophet Muhammad.
There are cases, however, where boundaries have been set. Last year, two Florida pastors were blocked from demonstrating outside a mosque in Dearborn, Mich., after a jury ruled it would have breached the peace. One of the pastors, Terry Jones, touched off a series of violent protests in Afghanistan that killed more than a dozen people after he burned a Quran in March 2011.
If anything, the cultural gaps may have been pried farther apart by the scope of the latest violence and bloodshed.
Google has refused a White House request to take down the video clip from its YouTube site. But it is restricting access in certain countries including Egypt, Libya and Indonesia, the world's most populous Muslim nation. A YouTube statement said the video was within its content guidelines. "This can be a challenge because what's OK in one country can be offensive elsewhere," it said.
At the same time, it's also opened fault lines within the Muslim world over what's an acceptable response. In many ways, it's simply an extension of the same internal struggles over Islam's moral compass that has gripped the faith for decades.
An Indonesian Muslim scholar, Komaruddin Hidayat, said Muslims have the duty to oppose to anything they deem offensive to their faith, but must "avoid using violence in expressing their objections." At the other end of the Muslim world in Nigeria, a top Islamic leader, Sheik Sani Yahaya Jingir, said violence never brings "any benefit to Islam."
For Jumaa al-Qurishi, a 38-year-old Iraq librarian: "This is not freedom. This is an act of aggression."
"Yes, we understand the First Amendment and all of this stuff," wrote Khalid Amayreh, a prominent Islamist commentator and blogger in Hebron on the West Bank. "But you must also understand that the Prophet [for us] is a million times more sacred than the American Constitution."
He adds: "As Americans have their own idiots and fanatics, we, too, have our idiots and fanatics. And as Americans are utterly unable -- probably unwilling as well -- to stop their idiots, we, too, are less able to rein in ours."
There's no wonder why the loudest voices still tend to rule the day, said Issandr El Amrani, a Moroccan-American journalist and visiting fellow at the European Center for Foreign Relations, a pan-European think tank.
"The resulting cascade of outrage is now predictable," he wrote in Abu Dhabi's The National newspaper. "Islamophobes in the West will say, ‘We told you they're fanatics,' and the crowd-riling demagogues here will say, ‘We told you they disrespect us.' And politicians everywhere will use the language of outrage in their petty calculations."
In Gaza, 23-year-old Rawhi Alwan described a cycle of mutual blame: "Some crazy Muslims will commit devilish acts to respond to the devilish sin."
Before he left for a peaceful Friday demonstration against the film, he changed his Facebook profile picture. It became an image pledging loyalty to Prophet Muhammad.
Associated Press writers Ibrahim Barzak in Gaza City, Adam Schreck in Dubai, Riaz Khan in Peshawar, Pakistan and Lara Jakes in Baghdad contributed to this report.