Earlier this month, Tunisian opposition leader Chokri Belaid was shot dead outside his home. Belaid’s death has shaken Tunisia, but it also illuminates larger trends in the post-revolution Arab world.

Belaid was an intrepid critic of the authoritarian ancien regime of Zine Abidine Ben Ali, which ruled Tunisia for nearly a quarter century until it was felled by a revolution in January 2011. He was also a leader of the left-wing Democratic Patriots’ Movement and emerged as a fierce foe of Ennahda, the moderate Islamist party that formed an uneasy coalition with two secular parties. But Belaid was unimpressed by that step, or by Ennahda’s promises to pursue moderate Islam and pluralism. He questioned the party’s sincerity about democracy and tolerance and also charged that it was either incapable of reining in—or sympathetic to—the agenda of Tunisia’s radical Salafis, who have used intimidation and violence in pursuit of their vision of a pure Islamic society, with their targets ranging from art exhibits and establishments serving alcohol to a university.

Belaid’s bluntness earned him death threats, and he worried openly about his safety. His widow and confidants charged that the government had failed to offer him protection, blaming Ennahda in particular. Other critics went further, insisting that Ennahda was complicit in Belaid’s murder, the party leadership’s condemnations of it notwithstanding. Both immediately after Belaid’s assassination and at his funeral there were massive demonstrations, clashes between police and protesters, and strikes. Tens of thousands participated in these activities, not just in Tunis, the capital, but in other cities as well.

The Clash Within Arab Societies

One of the larger trends illustrated by Belaid’s death is the controversy that surfaces whenever Islam’s role in politics and subsidiary issues—the content of the new constitutions, the role of women in politics and society, educational policy, the status of non-Muslims or the sale of liquor—are debated in the political arena.

The late Samuel Huntington proffered the “clash of civilizations” as a paradigm for understanding the post–Cold War world. But what we are witnessing in the Arab world, and not just since the recent revolutionary wave there, has been a clash within a civilization, especially when it comes to Islam’s place in politics.

The Islamist parties that were catapulted to power in Tunisia and Egypt by the momentum of the Arab Spring want the new political order to be shaped by the principles of their faith. But this project has run into resistance—not just from liberal democrats, socialists, and non-Muslim minorities, for whom this enterprise is anathema, but also from other Muslim groups, especially Salafis, who have chastised Ennahda and Egypt’s ruling Muslim Brotherhood for lacking commitment to a pristine sharia-based polity. For the Salafis, an Arab variant of what Turkey’s Justice and Development Party (AKP) has done amounts to a watery gruel at best.

Thus the struggle over religion’s place in politics has divided, rather than united, Muslims in North Africa and the Middle East. This split tends to be portrayed as a quarrel between “secularists” and “Islamists.” This is a mistake, for the former camp includes observant Muslims who, nonetheless, want to keep their faith and politics apart. Likewise, Christians and Islamic sects, such as the Sufis, take their religion seriously but do not want it to define political life, or for it to be defined by zealots claiming to be “true” Muslims.

Ruling Islamist parties have themselves been divided by the Islam-in-politics question. When Ennahda came under fire after Belaid’s murder, Prime Minister Hamadi Jebali proposed the appointment of a new cabinet consisting solely of professional technocrats, no doubt to calm things down by sidelining the controversy over Islam and politics. But as many of his Ennahda comrades saw it, this was no time to turn apolitical: Ennahda had placed first in the 2011 election based on a political platform shaped by Islam and retreating under pressure was unacceptable. Cabinet members belonging to Ennahda refused to relinquish their posts, and Jebali faced a revolt by members of his own party, who planned a rally to protest his plan. Adding to the confusion, Ennahda’s vice president, Abdelfattah Mourou, backed Jebali’s plan and called for the resignation of the party’s leader, Rachid Ghannouchi. And the prime minister, having threatened last week to quit if his efforts were blocked, did just that on Tuesday.

In Syria the clash within a civilization has assumed a deadly form. The civil war pits an Alawite-dominated state against insurgents, whose most pious members see Alawites not as fellow Muslims but as apostates. Bashar’s regime has been able to survive not only because it has more and better weapons than its foes (which it does) but also because other Muslims (Sunnis urban professional, Kurds, and Druze) and Syria’s various Christian denominations have either stayed neutral or backed the government despite their misgivings for fear that its fall will lead to the rise of a doctrinaire Sunni regime. The armed opposition is, in the main, Sunni, and has roots in the rural areas. Many groups within it are animated by the goal of establishing an Islamic state.

For now, the insurgents in Syria are held together by the shared commitment of destroying Assad’s regime, but the divisions over what precisely an Islamic political order ought to look like are already present and will surely deepen in a post-Assad state. So what we see in Syria is a split within what Huntington regarded as a single civilization (Islam) and tactical alliances that cross civilization boundaries.

The intra-civilization clash is also visible in Bahrain, where a Sunni-dominated monarchical state lords it over a restive Shia underclass, which constitute close to 70 percent of the population. Bahrain’s Shia rose up during the Arab Spring and continue to rebel (though without much notice from Washington, given that Manama, in Bahrain, is home to the U.S. Navy’s Fifth Fleet). What arguably saved the Bahrain’s rulers was the March 2011 intervention by Saudi troops, who quashed a rebellion rooted in the Shia community. Saudi Arabia was moved to act by its abiding fear of a fellow Islamic state, Iran, which it believed would become the patron a Shia regime in Bahrain.

Mobilization vs. Institutions

The second trend highlighted by Chokri Belaid’s murder, and by the Arab Spring more generally, is the imbalance between social mobilization (peoples’ newfound freedom to participate in politics) and political institutionalization (new political structures struggle to gain legitimacy, to provide venues for reconciling political disputes, and to maintain public order).

This is a feature of politics that Huntington got right in Political Order in Changing Societies, a book that, though not nearly as well known beyond the ivory tower as The Clash of Civilizations, is a far better one. The consequences of disequilibrium in the emerging political orders that Huntington depicted are clear in Tunisia and Egypt. Nascent institutions must manage energized and impatient citizens. Opposition parties that once led a marginalized existence, were banned, or whose leaders were jailed (or worse), have gained power only to find that they now have become the suspect establishment that the masses mistrust, with one difference: postauthoritarian politics enables public mistrust to morph more easily into popular mobilization.

But it is in Libya that the social mobilization-versus-political institutionalization dynamic is visible in its most dramatic form. A weak government struggles to create basic stability. Political institutions are feeble. A multitude of militias consisting of former anti-Qaddafi fighters are a law unto themselves. These armed statelets do not share a common agenda, bar the one of paying as little heed to the directives of the central government as possible, and that aggravates the chaos. So feeble is the center that it often relies on one set of militias to fend off challenges from others. But this has had two pernicious consequences: the state has become more dependent on militias, and violence among militias persists. The attack on the American consulate in Benghazi on September 11 that resulted in the killing of Ambassador Christopher Stevens and three other Americans—apparently the handiwork of a radical Islamist militia, Ansar al-Sharia—was but the most tragic example of the weakness of Libya’s institutions in the face of social mobilization.

Chokri Belaid’s killing was a particular (and particularly tragic) illustration of some of the larger forces that are now at play the Arab world—but are far from being played out.

Rajan Menon is the Anne and Bernard Spitzer Professor of Political Science at the City College of New York/City University of New York, nonresident senior fellow at the Atlantic Council and the author, most recently, of The End of Alliances. This piece first appeared in The National Interest.