The UN's commander in Damascus bid a miserable goodbye to his mission yesterday, unconvincingly claiming that the UN would not abandon Syria, but in fact turning the country into a free-fire zone the moment his last 100 soldiers begin their retreat tomorrow. Whenever the UN withdraws its personnel from the Middle East, calamity always follows in its wake – the departure of UN weapons inspectors from Iraq in 2003 presaged the Anglo-American invasion – and, privately, the UN fears the way is now open for the West and Gulf Arabs to pour heavy weapons into Syria to assist the rebellion against the Assad regime.

As General Babacar Gaye was standing in the lobby of the luxury Damas Rose Hotel, absurdly wishing Muslims a happy Eid holiday following the fasting month of Ramadan, and insisting that "the UN will not leave Syria", his own officers were packing their bags and queuing to pay their last hotel bills on the other side of the atrium. "They couldn't even wait until Lakhdar Brahimi got here to take over as UN envoy," one of Gaye's officials grumbled. The general declined to tell journalists whether more Syrian lives might have been saved if the UN stayed on.

To watch footage of UN staff preparing for their depature from Syria, click on the following links Link 1, Link 2, Link 3, Link 4

Outside, in the bright, hot Damascus afternoon, the often empty streets and shuttered shops spoke of lassitude rather than collapse. Bashar al-Assad's regime does not appear to be on the verge of departure – as American and French diplomats fondly believe – but the signs of dislocation are everywhere. Soldiers are billeted in the old Ottoman Haj station in central Damascus – from which no trains have left for Syrian cities in months – but the daily Syrian government-controlled press (there is no other) carries front-page stories from the war front each day. The capture of "Free Syrian Army" weapons, the assassination of civilians in and around Damascus – always attributed to "terrorists", of course – and fighting speeches by government acolytes make no secret of the nation's peril.

Perhaps for this reason, Syrians in Damascus speak with increasing freedom about the chances of the regime's survival, openly debating Bashar's victory or defeat in cafés and restaurants. All know that just a few miles outside the capital, a dark zone begins, a land – thousands of square kilometres of it – in which terrible deeds are taking place hourly. The main highways north have been cut and phone lines to Aleppo have largely collapsed; most travellers choose to fly to the city from Damascus, even though the road from Aleppo airport to the city centre is itself dangerous. Syrian Arab Airlines' main ticket office in Damascus was packed with passengers yesterday, all seeking flights out of the country or pleading for overbooked seats for relatives on planes from Aleppo.

And yet. The regime, whose history and roots go deep into the land of Syria – however brutal and corrupting its opponents believe those roots to be – seems to have more life in it than the Clintons and the Panettas and the Laurent Fabiuses of this world might believe. When French foreign minister Fabius – after listening to refugees' stories of atrocities in Syria – announces that Bashar al-Assad "doesn't deserve to be on this earth", his words appear infantile rather than threatening; indeed they sound like the kind of nonsense often spouted by Arab dictators. Damascenes are looking to their families rather than revenge; one middle-class man I have known for years told me yesterday how his wife worked for a government office but he had "moved her to home" so that she would be safe. The information ministry have produced a DVD packed with tapes of "terrorist" bomb explosions across the country – while admitting that the disk doesn't yet take in last week's truck bombing near the UN's hotel.

General Gaye's last goodbye was as bleak as it was short. After UN troops had arrived on 21 April to monitor the withdrawal of heavy weapons and a ceasefire, violence declined, he said, but "by the middle of June, it was clear that the parties were no longer committed to the ceasefire". UN observers then tried "to facilitate pauses in the fighting" to assist humanitarian work. "I call upon all parties to stop the violence which is causing such suffering to the Syrian people," General Gaye proclaimed, adding that humanitarian law must be respected.

But, needless to say, humanitarian law is not – and will not – be respected, and from tomorrow there will be no-one left to "facilitate pauses in the fighting". When I asked the good general how he personally felt about the failure of his mission, he replied that he was comforted by the fact that "the UN will stay in Syria". But this was preposterous. Save for a tiny UN office – with perhaps 10 staff – which has still not been approved, there is no UN observer mission left here, save for the post-1967 war UNTSO (UN Truce Supervision Organization) force which is fully engaged on keeping the Syrian-Israeli peace on the Golan Heights. The UN soldiers who have bravely sat through the shellfire of Aleppo and Homs will be there no longer.

Should the UN's Syrian mission have been led by a diplomat rather than a soldier – no-one here appears to understand why the Norwegian General Mood, General Gaye's predecessor, left his post – and should it have spent more time talking to opposition forces outside Syria, were questions still being debated within the UN yesterday. And why end the mission now? Because there were some in UN headquarters in New York who knew from the start that the assignment was not intended to succeed? Or because the Western nations and Gulf sponsors do not want UN observers snooping into the amount of new and more lethal weaponry which they may be planning to send to the "Free Syrian Army" and its more bearded allies in those parts of Syria in which Bashar's writ no longer runs?