Assad's exit opens a chance to rein in his backer Iran. Europe must seize it | Nathalie Tocci

With Iran suddenly weakened, some will demand regime change in Tehran. Europe's new chief diplomat should pursue nuclear deceleration instead

The fall of Bashar al-Assad in Syria is a momentous event, bringing to an end one of the most brutal dictatorships of the past half-century. But it does not automatically usher in reconciliation and democracy. To be clear: the Middle East was and remains on an escalation path, while Russia's determination to annihilate Ukraine as an independent country is unlikely to be affected by its humiliation in Syria.

Within Syria, violence, sectarianism and division are more likely scenarios than peace and stability, especially in the Kurdish-populated north, on which Turkish coercion is likely to increase.

Nathalie Tocci is a Guardian Europe columnist