When a dictatorship cannot regain control over a country in revolt for 18 months despite repeated offensives, when it cannot police the countryside away from the main roads, cannot secure the capital or its main trading hub, cannot even protect its innermost citadels and has to pull troops from its borders to protect its palaces, it is finished. This is the case with the dictatorship of Bashar al-Assad, who is still trying to kill his way out of the crisis, even as poorly armed rebels swarm through Syria’s cities and his supporters melt away. He is finished.

Last week’s insurgent bombing of his security cabinet in Damascus was devastating. He lost at least four of his top enforcers, including his brother-in-law, Assef Shawkat, the brains behind the Assad clan and reportedly also his cousin, intelligence chief Hafez Makhlouf, brother of Rami Makhlouf, the financier of the enterprise.

Of itself, the bombing is not a game-changer; the Assads still command far superior firepower. But its emblematic power is irresistible. On top of the stream of defections and desertions from the Syrian army, the regime now has to contend with informers who have infiltrated its inner sanctum. Until the July 18 attack, the Assads had managed to instil terror of retribution inside the castle walls. Now it is they and their entourage who are running scared.