The night before they blew themselves up outside the Iranian embassy in Beirut last week, the two suicide bombers stayed at the local Sheraton Hotel. Remind you of anything? Didn’t the 9/11 hijackers do the same, slept well in swish hotels before setting off to massacre the innocent? Just as the 9/11 men were of mixed nationality – most were Saudis but they included a Lebanese and an Egyptian – so at least the first of the two Beirut killers, the man who blasted down the Iranian embassy’s huge iron gate, was apparently Palestinian. And just as al-Qaeda in America went for symbolic targets – New York’s financial centre, the Pentagon, perhaps Capitol Hill – so the Beirut bombers went for the fulcrum of Iranian-Syrian-Hezbollah power in Lebanon, the embassy of the Islamic Republic.

And their intention was to demolish the Iranian compound in Beirut as surely as the al-Qaeda men destroyed the World Trade Centre. CCTV cameras around the Iranian embassy in the Jnah/Bir Hassan district of Beirut show clearly what happened in the seconds before 25 people – including the Iranian cultural attaché and four embassy guards - were killed. The first bomber, the one believed to be a Palestinian whose picture has been released by the Lebanese security forces, walked from his car and blew himself up, smashing the giant black-painted gate, while his accomplice waited in a Chevrolet TrailBlazer 4-by-4 containing 50 kilograms of explosive to drive inside the exposed compound and bring down the entire embassy.

But the man in the Chevrolet found himself temporarily blocked by a lorry carrying bottled water. The man in charge of the embassy’s security, Haj Reda, ran into the street with his colleagues – all of whom were Lebanese Shia, almost certainly belonging to the Hezbollah – to shoot it out with the attackers. Reda at once saw the water truck and, immediately behind it, the black Chevrolet, which started to move. He opened fire at once on the 4-by-4. At the same time, it appears, Corporal Haytham Ayoub, a young officer in the Lebanese Internal Security Forces – the government paramilitary police – chased the vehicle on foot and even tried to yank open the driver’s door. The driver then blew up the vehicle, killing instantly Reda and his four comrades and Corporal Ayoub – but failing to enter the compound.

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The details, which are emerging in Beirut each day, are important. The attack must have taken a lot of forward-planning – the Hezbollah, it should be added, believe that the Palestinian was one of the planners, not the first bomber wearing the suicide belt – and there is little doubt now that the Abdullah Azzam Brigades, an al-Qaeda ‘affiliate’, was behind the assault.

Al-Qaeda now has three main bases in Lebanon: in the northern city of Tripoli, where Sunni and Alawite Shia fighters have been shooting each other in a mini-civil war for months; among Sunni Palestinian groups in the Ain el-Helweh refugee camp in Sidon; and, most dangerously, in the north-east Lebanese border village of Ersal, which has become a rear base for Sunni rebels fighting Bashar al-Assad’s Syrian regime across the frontier in the Qalamoun region.

The Lebanese army is thus now regarded by al-Qaeda supporters of the anti-Assad rebels as being as much an enemy as Assad’s own forces. The army’s attempt to cut Ersal off from Syria accounts for the deaths of Lebanese troops outside the village, now swollen to twice its size by Syrian Sunni refugees. Just west of Ersal – inside Lebanon - runs the highway that links the Hezbollah-controlled town of Hermel and the largely Shia (and ancient Roman) city of Baalbek. New front lines are beginning to vein their way beside this road in north-eastern Lebanon, dividing Sunni from Shia, and criss-crossing the Lebanese-Syrian border.

Talk of the Syrian war ‘spilling over’ into Lebanon is therefore highly misleading. For in the north of the country, the original French Mandate-created frontier between the two countries – for the French created Lebanon out of Syrian territory after the First World War – is slowly ceasing to exist. North Lebanon is beginning to function, physically, as an Ottoman region again, the border a frame of mind rather than a barrier, as the sectarian conflict includes all in the region.

Thus the Sunni-Shia tragedy is spreading itself from the western border of Iran -- through Iraq and Syria and Lebanon -- all the way to the Mediterranean. The Iranians themselves acknowledge this quite openly while being deeply resentful of the Saudis as instigators of Salafist/al-Qaeda rebels in both Iraq and Syria and now Lebanon. And it was indeed curious that the Saudi ambassador should urge all his country’s citizens to leave Lebanon last week. Curious, because you would think it would be the Iranian (italics: Iranian) ambassador who would urge Iranians to leave Lebanon, not his Saudi opposite number. Surely, citizens of the country under attack are in more danger than others. Unless…

For the Iranians, last week’s attack on their Beirut embassy – notwithstanding the partial nuclear agreement in Geneva this weekend -- was serious enough, indeed far graver than it may appear to outsiders. The Lebanese reporter Scarlett Haddad was the first to realize that this was the first time in more than 30 years that Iranian interests have been attacked outside Iran. Hitherto, there appears to have been an unspoken agreement between Iran and its enemies: that while attacks may take place inside Iran – attacks on nuclear scientists in Tehran, for example, or in regional uprisings – the country’s external institutions were secure. No more.

The Lebanese military are beginning to suspect that within the various al-Qaeda groups that exist in the country, foreign intelligence agencies are at work – just as they were within Salafist al-Qaeda operations in Algeria, where the Algerian military and intelligence services are now known to have been deeply implicated in Sunni fundamentalist atrocities of the 1990s civil war. Was this why the Iranian ambassador blamed the “Zionist regime” for last week’s massacre in Lebanon?

The British have left their mark on Lebanon’s new £50,000 note

For those who believe that the Lebanese are haunted by danger, they are also blessed in having probably more public holidays than any other nation on earth. We Brits have a paltry eight (more, for instance, if you live in Northern Ireland), the Americans have five (though individual states enjoy more) and the Egyptians around 11. But the very sectarian nature of Lebanon means that everyone must celebrate 17 public holidays -- Christmas and Easter and the Armenian Christmas (in January), as well as the Prophet Mohamed’s Birthday, the Muslim Eid al-Adha feast, and sundry other religious and secular commemorations – for the nationalist Martyrs of 1916, hanged in Beirut and Damascus by the Ottomans, for Liberation (from the Israelis in 2000) and for Independence from the French, whose 70 anniversary was celebrated last Friday.

Which is why many Lebanese suspect that the defects in the new 50,000 Lebanese pound note (about Sterling Pounds 20) to mark the country’s 70 birthday symbolises the dysfunction of their nation. The two official languages of Lebanon are Arabic and French. However, printed in Britain (of course), the new notes refer to “l’independence” – with an acute accent over the first ‘e’ but with the third ‘e’ spelling the word in the English manner rather than the correct French (with an ‘a’). Even the orthography of ‘50,000’ is written thus – rather than the French ’50.000’. But fear not, even the governor of the Central Bank admits they’ll become collectors’ items.