DURHAM, N.C. — In setting himself ablaze following a humiliating encounter with the police, the university-educated Tunisian vegetable seller Mohamed Bouazizi triggered a wave of protests across the Arab world. Several Arab dictators who had held power for decades have already been ousted or forced to announce that they will retire.

But protesters in Cairo, Tunis and Sanaa want much more. They also seek efficient governance, economic reforms to stimulate growth, the ouster of collaborators, democratic rights, freedom of religion (and perhaps also from religion) — in short, a comprehensive social transformation.

Everywhere, incumbent regimes have mounted resistance. The unforgettable scene of camel- and horse-riding Mubarak supporters beating tech-savvy Egyptian protesters signals that the old order will not yield without a fight.