I was just thinking that Damascus was a lot quieter than six months ago – at that time the sound of government artillery pounding the rebel-held districts resounded daily across the capital – when there was the crash of a mortar bomb exploding a few hundred yards away. Fired from a rebel area, it had landed in Bab Touma, a Christian part of the Old City, where I am staying. It turned out not to have killed anybody, unlike the last time I was here, when a couple of mortar rounds landing in Straight Street killed four people.

“Things have not changed much since last summer,” said a local businessman. “The biggest change is that people are more used to living in a permanent state of war in which survival is the main objective in life. After all, we are entering the fourth year of fighting.” He also admitted that there were fewer exchanges of fire between government and opposition districts in which the Syrian Army uses by far the heavier weapons. But he did not expect the present military deadlock to change radically and he added: “We do not expect much from the Geneva II talks.”

The fighting has eased somewhat around Damascus in recent weeks. This is in large part because the rebels are fully engaged in fighting their own “war within the civil war”, pitting a disparate coalition of rebels against the Islamic State of Iraq and the Levant (Isis) in a struggle that killed 1,395 people in the first three weeks of January. Isis has retaken the one rebel-held provincial capital, Raqqa, and is insisting that women wear the niqab, the all-enveloping cloak and veil, and has banned music, pictures and cigarettes.

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But when fighting does take place between government and rebel forces, it has lost none of its previous viciousness. When jihadi fighters stormed Adra on the north-eastern outskirts of the capital in December they reportedly killed workers in a local bakery by cooking them in their own ovens, while doctors and nurses in the local clinic were executed for working for the government. Heytham Mousa, the head of the legal department in the Ministry of Information, was taken away with his wife and daughter by rebels. None has been heard from since and calls made to his phone are answered only by a voice saying it is now in the possession of Jabhat al-Nusra, the Syrian al-Qa’ida affiliate.

The government has gained a little from the rebel groups murdering each other and, such is the intensity of hatreds within Syria, has probably lost little credit domestically from the disclosure of pictures allegedly showing 11,000 prisoners tortured or starved to death. Syrians on both sides are inured to atrocities. But the depth of division within the opposition is now so great that it is difficult to see how its negotiating team in Geneva could deliver on practical questions such as ceasefires, prisoner exchanges and the delivery of aid. Indeed, the rebel negotiators would risk of execution as traitors if they set foot in much of rebel-held north and east Syria.

But the government also has its weaknesses: it has not taken advantage of the rebel civil war to advance, except in a few areas around Aleppo and limited parts of Damascus. One explanation for this might be that it does not want to threaten the rebels and unite them while they are doing the government’s work for it by killing each other. But it is also true that the government’s forces are already over-stretched, without enough troops and not capable of launching offensives on very many different fronts. There is evidence for this in that Jabhat al-Nusra has reportedly captured, for the second time, the ancient Christian town of Maloula. This is just off the crucial main road north from Damascus to Syria’s third city, Homs, and the fact that the government cannot permanently secure this important route shows that it is not strong enough to counter-attack. The Homs-Damascus road was also shut for 17 days recently when the opposition’s forces took the town of Nabq half way along it and is till not wholly secure.

The government has been besieging rebel-held districts in the capital with the aim of starving them out. Some, such as Barzeh in Damascus, are once again partially under government control after deals in which heavy and sometimes light weapons are handed over by rebels. But these agreements are fragile because terms, such as those to do with freeing prisoners, may not be abided by. Some rebel bastions such as Douma, north-east of Damascus, have big reserves of food to hold out for a long time. In most of these much fought over districts, the population has largely fled and shows no signs of returning. The people who left are sleeping rough in parks or are crammed into apartments while, just across the border in Lebanon, businessmen are charging $200 a month in rent for tents in which Bedouin and seasonal labourers once lived.

By contrast, the government-held districts maintain what on the surface looks like a normal life. There is a plentiful supply of bread at subsidised prices, as well as gasoline and cooking gas. Traffic is appalling because of numerous checkpoints and what used to be a 10-minute journey can take an hour; but the government still pays salaries and pensions to its employees, even if prices have soared in the markets. It remains less dangerous in central Damascus than it is in Baghdad, with its daily onslaught of bombs aimed at civilian targets.

Overall, it is difficult to see ceasefires being put in place and maintained without the presence of UN monitors who can act as mediators and conduits for the exchange of information between people who have been trying to kill each other for three years. Under the plan of the former UN Secretary General Kofi Annan in 2012, UN monitors played a significant role in reducing the violence, but at the time both sides were still hoping for a military victory and saw the ceasefire as a temporary truce. The best that can be hoped for probably is temporary ceasefires and truces but these are not to be sneered at. One Lebanese academic notes that in the 15 years of civil war in neighbouring Lebanon, between 1975 and 1990, there “were over 600 ceasefires, which may sound ridiculous but a lot of people are alive because of them who would have died if they had not been there”.

The government now looks to be in a stronger position than the rebels. The US and the Europeans have become increasingly worried by the successes of Isis and Jabhat al-Nisra, as well as the jihadi groups that have come together to form the Islamic Front. Though the various jihadis may differ in their tactics, their world view is very much the same. One close observer of the opposition, who recently returned from travelling in the rebel-held areas of northern Syria, says that “you could go an awful long way talking to these jihadi groups before you met any fighters who did not thoroughly approve of 9/11 as a well-deserved blow against the US”. American efforts to talk to jihadis who they deem to be free of al-Qa’ida links look as ill-considered in Syria as they turned out to be in Benghazi before the US ambassador was murdered.