Two things stand out in the Middle East since the Arab Spring began — one that happened, and one that did not. What happened was that for the first time in modern Arab history, authoritarian regimes and rulers were toppled, or seriously challenged, by popular demonstrations, not — as in the past — through military coups.

But what did not happen might be as important as what did. While dictators associated with military juntas were challenged overnight, the Arab Spring never came to the region's conservative monarchies. The dynastic rulers of Morocco, Jordan, Saudi Arabia and the Persian Gulf states (with the exception of Bahrain) remain more or less firmly in the saddle, even though Saudi Arabia's regime, at least, is in many respects far more oppressive than were the former Egyptian and Tunisian regimes.

Of course, oil money helps to sustain autocracy, but this is not a factor in Morocco and Jordan. It appears that these monarchies enjoy a form of traditional authority that the region's secular nationalist rulers never had. Being descendants of the Prophet, as in Morocco and Jordan, or having custodianship of the holy sites of Mecca and Medina, as in Saudi Arabia, bestows a legitimacy on the countries' rulers that is linked to Islam.