Leading article: Restraint remains the West's best policy

It has been a bad few days for the two most egregious tyrants in the Middle East. In Libya, the net is tightening around Colonel Muammar Gaddafi. Now President Bashar al-Assad is under unprecedented pressure to end his savage crackdown in Syria, which has killed more than 1,800 people in the past five months.

Yesterday, the United Nations suggested that the abuses perpetrated by the Damascus regime against unarmed civilians amounted to crimes against humanity that should be referred to the International Criminal Court. At the same time – and long overdue – the US explicitly demanded that Mr Assad step down and announced further sanctions to deepen the isolation of his government. Most importantly, Muslim countries in the region including Jordan, Saudi Arabia and, above all, Turkey, Syria's most important trading partner, have said that enough is enough.

Inevitably Mr Assad's promise yesterday, a day after his security forces had killed 20 more protesters, will be greeted with scepticism. The president's offers of "reform", insofar as they may be termed such, have consistently been far too little and far too late.

But Hillary Clinton, the US Secretary of State, is correct to insist that this is a matter for the Syrian people to decide, without direct Western intervention – even on the relatively modest scale seen in Libya. The Syrian opposition is even more fragmented and disorganised than its counterpart in Libya.

The US learnt to its cost how combustible the ethnic and sectarian mix in Iraq was once a repressive dictatorship was toppled. The mix in Syria is at least as volatile, even leaving aside the country's central role in the Israeli-Palestinian conflict, and the risk of direct confrontation with Iran, Syria's chief ally and the Middle East's prime mischief-maker. But finally, Mr Assad's days now seem numbered.