CHARLESTON, W.Va. -- Time after time, deadly violence erupts in various Muslim nations because of perceived religious insults.

After U.S. troops inadvertently burned some discarded Qurans in Afghanistan, rioting killed 30 Afghans and six American soldiers. Four of the murdered Americans were shot by supposed "friendly" Afghan colleagues.

After a Danish newspaper printed cartoons of the Prophet Muhammad, weeks of rioting killed dozens of people -- including six in a suicide bombing of the Danish embassy in Pakistan.

After the novel The Satanic Verses contained a dream sequence lampooning the Prophet, riots exploded in numerous countries and a $2 million reward was offered for  the assassination of author Salman Rushdie.

Now it has happened again. A low-budget movie "Innocence of Muslims" depicts Muhammad as a fraud, womanizer, child abuser and massacre-perpetrator. One backer was Florida evangelist Terry Jones, whose public Quran-burnings caused days of rioting in Afghanistan. Such amateurish films usually have little impact -- but a 14-minute trailer was posted on the Internet, and it flashed through the Islamic world.

America's ambassador to Libya and three diplomatic aides were killed in an attack on a U.S. consulate. Protesters also stormed the U.S. embassy in Cairo, but caused no injuries. Palestinians in the Gaza Strip burned American flags and chanted "Death to America."

President Obama beefed up security at embassies overseas and declared: "While the United States rejects efforts to denigrate the religious beliefs of others, we must all unequivocally oppose the kind of senseless violence that took the lives of these public servants."

When the protests began, the Cairo embassy issued a statement condemning "misguided individuals" who slander Muslims. In response, Republican challenger Mitt Romney said it was "disgraceful" for the Obama administration "to sympathize with those who waged the attacks." Good grief -- must everything be turned into a campaign hatchet-job?

The new upheaval, like previous ones, raises concern that some Muslim societies aren't yet stable enough for democracy. After last year's "Arab Spring" uprisings, Western nations hoped that popular government and human rights would grow in places formerly ruled by military dictators.

The new violence "underscores the threat of unchecked religious fanaticism," theChristian Science Monitorsaid Wednesday.

Moderate leaders in Libya declared that the killings were perpetrated by an extremist fringe, while the majority of Libyans want a peaceful democracy. Secretary of State Hillary Clinton said: "This was an attack by a small and savage group -- not the people or government of Libya."

Middle East expert Juan Cole at the University of Michigan said radical jihadists have been bypassed in the wave of Arabic uprisings, so they're causing trouble.

"One way the fundamentalist vigilantes can hope to combat their marginalization and political irrelevance in the wake of the Arab Spring is to manufacture a controversy that forces people to side with them," he wrote.

Despite the grotesque Libyan violence, we hope fundamentalist vigilantes continue to lose power in Islamic nations, and genuine democracy slowly develops.