On the 11th anniversary Tuesday of the 2001 terrorist attacks on the World Trade Center and Pentagon, events in Northern Africa once again reminded the nation what a volatile world it confronts. And for all its promise of new beginnings, the Arab Spring has added to the volatility.

U.S. embassies in Cairo, Egypt and Benghazi, Libya were overrun by angry mobs upset by the appearance on the Internet of a video that purports to be the trailer for a hate film called the "Innocence of Muslims." The amateurish production denigrates the Prophet Muhammad. While the video is virtually unknown domestically, it got the attention of the Arab Street, where angry Muslims saw it as evidence of United States disrespect.

While the attack in Egypt appeared to be the result of the impulsive reaction of a mob to the hateful video, the actions in Libya may be more troubling and menacing. There the attackers were armed with mortars and rocket-propelled grenades. United States and Libyan authorities are now investigating whether anti-American forces saw anger over the video as an opportunity to launch the attack.

That attack resulted in the killing of Ambassador J. Christopher Stevens and three other diplomats. Ironically, Mr. Stevens had worked with and been praised by the Libyan rebels who, with the help of NATO air support, had brought about the fall of dictator Col. Muammar el-Qaddafi last year.

It is no coincidence that the civil unrest and attacks on American embassies occurred in two nations just recently free of their iron-fisted tyrants, in Libya, Qaddafi, and in Egypt, Hosni Mubarak. While oppressors of the people, they did keep order and assure relative stability, a major reason why Western leaders were so long willing to cooperate with and tolerate their rule, particularly Mubarak.

It is still unclear how the Arab Spring will proceed, with moves toward pluralism or degeneration into militancy and intolerance. Al-Qaida stands eager to exploit voids in authority and Syria, in particular, is awash with armed militias from various tribal factions.

The incidents displayed once again the enormous canyon between U.S. principles of free speech and expression and the Arab world's perception that some things are beyond tolerance, chief among them religious insults toward Islam and its prophet. Illustrating this, the Muslim Brotherhood, sponsors of the first elected president to follow Mubarak, Mohamed Morsi, issued a statement calling upon the United States to prosecute those responsible for the video. The concept that this nation does not prosecute people for what they say, no matter how reprehensible or irresponsible, appeared to be beyond the group's comprehension.

Reacting to these attacks, while trying to move the revolutions in the Arab world in the right direction, will require a deft foreign policy touch. President Obama pledged to work with the Libyan government to bring the attackers to justice. But he also made it clear that the United States, in the wake of Qaddafi's fall, cannot afford to turn angrily away from Libya.

Secretary of State Hillary Clinton sounded the right balance in stating that violent actions are never justified in response to disrespectful speech.

"America's commitment to religious tolerance goes back to the very beginning of our nation. But let me be clear, there is no justification for this. None. Violence like this is no way to honor religion or faith," she said.

Lastly, we join many others in noting how inappropriate it was for Republican presidential candidate Mitt Romney to try to exploit this ugly situation for political gain, firing off a press release critical of the administration's actions, even while the crisis and the attacks on U.S. interests were continuing. And in the process, no less, his campaign violated an agreement to hold off on political attacks during the 9/11 anniversary. Mr. Romney should be ashamed.