Amir Taheri is always worth reading:

Israel is not fighting to hold or win more land; nor is Hezbollah. But both realize that they cannot live in security and prosper as long as the other is in a position to threaten their existence. A Middle East dominated by Islamism could, in time, spell the death of Israel as a nation-state. A westernized, democratic Lebanon, on the other hand, could become the graveyard of Hezbollah and its messianic ideology. And if the US succeeds in fulfilling George W. Bush’s promise of a “new Middle East” there will be no place for regimes such as the Islamic Republic in Iran and Syria’s Baathist dictatorship.
The present rupture in Lebanon has much to do with who will lead the fightback against the West. For almost a quarter of a century there has been intense competition within the Islamist camp over who could claim leadership. For much of that period Sunni Salafist movements, backed by oil money, were in the ascendancy. They began to decline after the 9/11 attacks that deprived them of much of the support they received from Arab governments and charities. In the past five years Tehran has tried to seize the opportunity to advance its own leadership claims. The problem, however, is that Iran is a Shia power and thus regarded by Sunni Salafists as “heretical”. To compensate for that weakness, Iran’s President, Mahmoud Ahmadinejad, has made the destruction of Israel a priority for his regime. The war triggered by Hezbollah is in part designed to show that President Ahmadinejad is not bluffing when he promises to wipe Israel off the map as the first step towards defeating the “infidel” West.
Iran’s “supreme guide”, Ali Khamenei, expressed a similar view this week during an audience he granted in Tehran to Hugo Chavez, the Venezuelan President. ”What we see in Lebanon today represents the revolt of Muslim nations against America,” he said. ”Hezbollah is backed (by Iran and others) because it is fighting America.” President Chavez endorsed that analysis by calling on Muslims and non-Muslim revolutionaries to unite to “save the human race by finishing the US Empire”.
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Tehran believes that a victory for Hezbollah in Lebanon will strengthen President Ahmadinejad’s bid for the leadership of radical Islam. A number of recent events have made his attempt to wrest control more likely. This week several leading Sunni theologians at the Al-Azhar seminary in Cairo issued fatwas that allow Sunnis to fight alongside and under the command of Shia Muslims. The fatwas came in response to a Saudi fatwa that had declared any association with and support for Hezbollah to be haram (forbidden).

More here.