It was a bomb against the Saudis. Mohamad Chatah represented the most reasonable face of the Saudi-supported March 14 party in Lebanon – moderates are usually the first targets of Lebanese assassins – and the bombing in which six others, including the former finance minister’s bodyguards, were killed, was carried out with the usual meticulous planning. In the very centre of Beirut, too, in the new city built by Saad Hariri’s father Rafiq and within half a mile of where Rafiq himself was assassinated almost nine years ago.

As usual, the killing was condemned by all the usual suspects: the Syrians, the Hezbollah, the Russian embassy, the Iranian embassy and just about anybody who might have wanted to strike the political party of Lebanon’s Sunni community. Last month, a Shia Muslim Hezbollah man was murdered outside his home, before that the Iranian embassy was bombed with 26 fatalities, before that the Shia southern suburbs, before that two mosques in Tripoli (Chatah’s home town), total dead 46. Tit-for-tat isn’t the word for it. Mohamed Chatah had been a financial adviser to Hariri father and son – and must have known that he was, like many good guys in Lebanon, a target.

Several years ago, I met him in a West Beirut restaurant – ironically in the same Ein Mreisse district in which he was to die – and he was trying to decide then if he should leave his post at the International Monetary Fund in the US for the cantankerous, dangerous, addictive world of Lebanese politics. My host was trying to persuade him to make the journey back to Beirut – he may regret this now, since his advice led Mohamed Chatah to his martyrdom – and Chatah came across as an eminently moderate man who believed in dialogue rather than military force, even when it came to disarming the Shia Hezbollah militia. He was, as his friend Marwan Iskander said to me yesterday, a man of integrity. And integrity is a rare quality in Lebanon.

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Like most of Lebanon’s finest, he had been educated at the American University in Beirut but gained his doctorate in the States where he would later serve as Lebanon’s ambassador. Diplomat and politician, his death caused the March 14 movement to blame Hezbollah and the Iranians. Najib Mikati, the caretaker prime minister in a Lebanese government that doesn’t exist, claimed that Lebanon was now a “hostage to terrorists.”

Oddly, Arabs – from General Sissi in Egypt to Messers Assad and Maliki in Syria and Iraq – now use the word ‘terrorist’ more frequently than the Western mentors who taught them to use this meretricious, generic and frightful expression. But in Lebanon, it is difficult to dispute the fact that violence has always imprisoned the Lebanese. Indeed, the killers of this tiny state make a point of eliminating all those who might cure Lebanon’s cancer peacefully – hence Chatah’s murder – thus leaving the field open to the wild men of every party.

Up to 70 Lebanese were also wounded in yesterday’s bombing – which may or may not have been a suicide killing – and none missed the obvious fact that the assassination occurred in one of the most heavily guarded central areas of new Beirut. Surrounded by banks, boutique shops, ancient churches and mosques and the prime minister’s own offices – all restored by Hariri senior after the country’s 1975-90 civil war — Mohamed Chatah was a prestige target in a prestige part of town. The smoke of the explosion which killed him drifted across the facade of the old Turkish serail in which the caretaker cabinet – the prime minister-designate has not been able to form a government for eight months – regularly meets. In Lebanon, democracy often comes shrouded in smoke and fire.

Mohamed Chatah, as everyone in Lebanon knew, opposed both the rule of President Bashar al-Assad of Syria and the Hezbollah’s armed role in Lebanon. Scarcely an hour before his death, he had tweeted a warning that the Hezbollah was “pressing hard” to be granted the same security and foreign policy powers once enjoyed by Syria. He had several times written that “a united and peaceful Syria ruled by Assad is simply not possible.”

As long ago as 2007, on the eve of presidential elections, Mohamed Chatah had talked of the assassinations still to come in his country.

Yet it would be naive to think that these views – freely expressed by many in the Lebanese opposition, some more prominent than Chatah himself – provoked his murder. In reality, he was just another face of the Sunni-Shia cold war which has burst through the crust of Muslim society over the past 30 years, increasing in ferocity as the old American-Soviet Cold War faded into history.

It is easy to forget that until the Iranian Revolution – which brought the power of Shia Islam into perspective within the Middle East – Saudi Arabia was virtually the only focus of Muslim attention. The holy cities of Mecca and Medina ruled the Islamic world; once the Iranian clerics of Tehran and Qom claimed the latest Muslim revolution in 1979, Saudi Arabia was challenged.

Thus in Iraq and Syria as well as between Saudi Arabia and Iran itself, the Sunni-Shia conflict – so long deep-frozen by the East-West Cold War and scarcely spoken of within the Middle East for fear of its repercussions – has boiled over into a terrifying and real war. Insofar as Syria’s sectarian battle has infected Lebanon, poor Mohamed Chatah was a victim of this same conflict, slotted neatly and fatally into the Saudi-Iran struggle made manifest in one of the region’s smallest countries.