Is the agreement important?
It is very significant inside and outside Syria because it is between the US and Russia, the most powerful players in the Syrian conflict, who can put pressure on their allies and proxies to comply. It is important too because it is the sign of a change in the international political landscape: Russia is back as a superpower – certainly in the Middle East and perhaps globally – for the first time since the fall of the Soviet Union in 1991. The intention of US and Russia to closely cooperate in a joint air campaign against Isis and Jabhat al-Nusra, the Syrian branch of al-Qaeda now relabelled as Jabhat Fateh al-Sham, is unprecedented.
Will the Syrian government of President Bashar al-Assad keep the ceasefire?
Yes, because it has said it will and is dependent on Russian air support and weapons supply. But, equally important, it is in its interests to do so because the US and Russia will be targeting al-Nusra, the Salafi-jihadi movement which is the main fighting arm of the non-Isis rebel movement. It has been in the forefront of all successful rebel offensives. If the armed opposition no longer contains al-Nusra and Isis, then it will be substantially neutered when it comes to fighting the Syrian Army and its allies. This is a big gain for Assad.
More immediately, a ceasefire which freezes the present battle lines in place is also in his interests because his forces have once again encircled rebel-held east Aleppo, taken over the rebel stronghold of Daraya in Damascus and are advancing on other fronts. The Syrian Army probably feels that it can do with a period of consolidation and will be able to focus its forces against a weakening Isis and make territorial gains in east Aleppo.
Could Iran, Hezbollah and the Shia axis play a spoiling role?
The Iranians have welcomed the agreement and, since their main aim is to keep Assad in power, it is in their interests, as it is in his, to go along with the agreement.
So who loses out in this agreement and is there anything they can do about it?
It is bad news for Isis because the coalition against it will get even bigger. But already there are more planes and drones in the sky in Syria and Iraq than there are targets to attack. The military onslaught from the air against Isis may not be that much heavier, but the Syrian army will be freer to attack it east of Aleppo and elsewhere. There is not much Isis can do about this.
How will al-Nusra react to being targeted along with Isis?
Here is one the weaknesses of the agreement. The non-Isis armed opposition in Syria has long been dominated by Islamists, but the Islamists fighting groups are dominated by Nusra. Its discipline, high morale, experience, popularity and, perhaps most important, ability to deploy suicide bombers in large numbers, make it the backbone of armed opposition. But the US and Russia envisage the “moderate” opposition distancing itself geographically from al-Nusra which will then be bombed by the US and Russians. But why should al-Nusra wait for this to happen? For them, the peace plan agreed in Geneva is a war plan directed against themselves. In other words, they have no incentive to cease firing and, even when backed by US and Russian airstrikes, there is no moderate opposition fighting force strong enough to replace them. Some al-Nusra leaders may well feel that if they are going to be treated like Isis, they might as well think about establishing better links with that organisation – though it will be difficult for them to forget the inter-jihadi civil war of 2013-14.
Will the UN aid convoys get through to besieged cities?
Yes, this is an essential part of the agreement – particularly aid for rebel-held east Aleppo. In the murky whirlpool of competing crises that make up the Syrian crisis, one aspect that has made an impression on the outside world is people starving while encircled by their enemies. This is certainly happening, but not on the scale that people imagine. The 250,000 to 275,000 people in east Aleppo have not run out of food yet – though it is expensive – because the UN has prepositioned supplies there that are being run down, but they need to be topped up. The other big rebel enclave, Eastern Ghouta east of Damascus, has many shortages such as seeds and agricultural machinery, but it is a fertile area that grows much of its food. But there are rebel areas where people are literally starving such as Madaya and Moadamiya. All these are likely to be relieved, but there may be difficulties over Kefraya and Foua, two pro-government Shia villages west of Aleppo whose fate is linked to the rebel-held Madaya and Zabadani west of Damascus.
Will the bombing of civilian areas by the Syrian air force stop?
Yes, because public opinion abroad is very conscious of this and the Syrian air force will not be allowed to operate over these areas. In any case, the barrel bombing of civilian areas never did the Damascus government much good militarily. Its main purpose was to force a mass exodus of people from any area held by the opposition.
Will the war end?
No, because the US-Russian agreement contains a peace plan and a war plan. The war is to be waged against Isis and Nusra, but it is not clear where the ground troops to do will come from.
Could the whole agreement come unstuck?
Yes, because not everybody acts in their own interests – this is a good deal for Russia, Iran and the Syrian government – but a damaging one for the opposition. Put simply, it does not have a credible military force capable of replacing al-Nusra and Isis as opponents of the Syrian government.