What's in a telephone dialling code? Phone calls from Beirut to Damascus used to be preceded by the international code - 00 96311 - but a simple 02 now suffices. From the Syrian to the Lebanese capital, I now dial 061 instead of 00 9611. The message is clear: Syria is not a foreign country.
Ireland is familiar with the political significance of phone numbers: Dublin to Belfast is a trunk call, symbolising the unity of the island. But in the other direction, Belfast to Dublin is an international call.
President Hafez al-Assad, who died on June 10th, used to say that the Syrians and Lebanese were "one people in two countries".
Ever since Syria dispatched troops to civil war in Lebanon in 1976, there has been talk of the "Syrianisation" of Lebanon, of "creeping annexation". When I drive to Beirut airport, I have to pass down the Boulevard du President Hafez el-Assad, beneath a marble-clad obelisk in his honour.
In the aftermath of Assad's death, the Lebanese government banned French newspapers that criticised him. Beirut takes no important decisions without consulting Damascus. Yet, in 24 years, Syria has never imposed its currency or flag. As the British writer Patrick Seale says, Lebanon needs Syria for security, stability and to preserve its Arab character.
Isolated Syria needs Lebanon as an opening to the outside world, for the tourists it attracts and the banks where rich Syrians keep their money.
Assad's death and last month's Israeli withdrawal from southern Lebanon have brought the whole question into more painful focus.
Even pro-Syrian Lebanese believe that with Assad gone, Syria's grip on Lebanon will weaken. So far, it's not proving true.
Damascus - not Beirut - is sticking to the "not one inch of Arab land" principle in refusing to recognise Israel's withdrawal from Lebanon as complete.
It was to thank Syria for joining the anti-Iraq coalition in 1990 that the world - including the US and Israel - gave tacit agreement for the October 1990 bombing by Damascus of the Lebanese presidential palace at Baabda, where a mad general had directed artillery fire for nine months from his bunker, shelling what he called the Syrians' Muslim Lebanese "collaborators" in west Beirut.
Since the routing of Gen Aoun, Lebanese governments are designated in Damascus and there is no real political life here.
The Lebanese get on with what they always did best: making money.
Any Syrian will tell you that President Assad saved Lebanon, that Syria made tremendous sacrifices for the good of Lebanon. In Beirut, the range of emotion is much broader - from abhorrence of Syria to sycophantic devotion - but the majority of Lebanese regard the Syrian presence here as a necessary evil.
Facts and figures about Syria's presence - many Maronite Catholics call it "occupation" - are more complicated than the telephone codes. Decades ago, a Western wire agency estimated there were 35,000 Syrian troops in Lebanon. Although neither Damascus nor Beirut ever provided an official statistic, the number stuck, despite the departure of more than 10,000 soldiers in the mid-1990s.
Who knows how many Syrian plain-clothes mokhabarat are here? But since the Lebanese and Syrians pooled their intelligence operations a few years ago, Lebanese agents do most of the dirty work.
Nor is there any agreement on the number of Syrian labourers in Lebanon. It is easy to recognise them on the streets of Beirut - darker-skinned than the Lebanese, with slicked-back hair, baggy trousers and garish coloured shirts; poor young men from the desert near the Iraqi border, bachelors who stay for six months or a year to earn money.
A pro-Syrian Lebanese newspaper editor tells me there are at most 400,000 Syrian workers in Lebanon, 10 per cent of the population. If the Syrians did not do construction work, street sweeping and itinerant vending, he argued, it would be done by Sri Lankans or Filipinos - because the Lebanese never did menial tasks.
But the Maronites who clamour for Syria's departure claim there are up to 2 million Syrians in Lebanon, and that they are taking jobs from the Lebanese. And Assad's death has made the Maronites bolder in demanding a Syrian departure.
Colonialism has a lot to answer for. The Lebanese have always been divided between pro-French Maronites - for whom Paris created the State of Greater Lebanon in 1920 by amputating large parts of Ottoman Syria - and the Muslim Arabs, who felt they were part of Bilad al-Sham or "lands of Damascus".
At the antiquarian bookshop in Makhoul Street, I've bought sepia postcards stamped "Beirut, Syria".
Between 1919 and the end of the French mandate in 1946, the majority of Lebanese several times asked for union with Syria; they told the League of Nations'King-Crane commission the same thing. But France and Britain were determined to carve up the Middle East. The rest, as they say, is history.
