Governments from Morocco and Algeria along the Mediterranean coast to Egypt, Jordan, Syria and the Gulf will be watching Tunisia with alarm. These are diverse states, but with common features: ossified politics and corrupt elites, lacking any governing principle other than the urge to resist demands for change from liberals and Islamists. They also suffer from cultural and academic sterility – the suffocation of free thought that might seed political and social renewal.

Stability for such regimes relies on a combination of state force and public apathy. It is the latter that changed so markedly in Tunisia. Especially worrying for other Arab leaders will be the fearlessness of the crowd, prepared to confront riot police firing live rounds. Authoritarian regimes rarely survive for long once the illusion of invincibility is shattered.