It is good that international donors have pledged $7.6 billion to help rebuild Lebanon after last summer’s devastating Israeli air strikes. The democratically elected government of PM Fouad Siniora needs all the help it can get.

Clashes between Shiite supporters of Hezbollah and the government’s mainly Sunni supporters threaten to overwhelm Siniora’s fragile coalition. If not contained, they could even reignite Lebanon’s catastrophic civil war. Lebanon’s fundamental problem is the archaic and unfair political system that divides the country’s top offices among rival and distrustful religious communities. Lebanon’s large and impoverished Shiite minority, long a major loser in this system, has been increasingly radicalised — straight into the arms of Hezbollah.

Hezbollah has close links to Iran, which supplies its weapons and cash, and Syria, which provides safe passage for those weapons and more. Any plan for stabilising Lebanon has to face up to this dynamic.

That’s why the Bush administration needs to drop its stubborn resistance to diplomacy with Syria and try to coax Damascus away from both Iran and Hezbollah. Engaging Syria may not work. But ignoring it all guarantees that even $7.6 billion in aid will not be enough to stabilise Lebanon.