Bangladesh, Jan. 12 -- History is rarely kind to societies that mistake collapse for liberation. Iran today stands at precisely such a crossroads. As nationwide protests intensify—from Ilam and Luristan to Kermanshah and beyond—the question dominating Western capitals and exile circles alike is not whether the Islamic Republic can endure, but what might replace it. That question, however, is being answered far too hastily, and dangerously so. For Iran, the temptation to leap from mullaism back to monarchism would not be a cure. It would be a relapse.

The Islamic Republic is unquestionably exhausted. Its legitimacy has eroded under the weight of economic decay, moral hypocrisy, and relentless repression. Yet regime failure doe...