UN envoy Staffan de Mistura effectively holds the US and Russia responsible for the escalation in the Syrian conflict, blaming the stalling of ceasefire talks on "the ambiguity about al-Nusra and the issue about grounding the Syrian air force".
US secretary of state John Kerry exacerbated differences between the two powers by expanding the demand for grounding of Syrian war planes to include those of Russia. This demand is rejected by Moscow, Damascus and Tehran. The latter has reinforced the Syrian army with ground troops.
The Syrian government responded to the failure to reach agreement on a cessation of hostilities by launching a fresh offensive against insurgent-held eastern Aleppo, allowing an aid delivery to the Damascus suburb of Muadamiya, and evacuating 150 insurgents and their families from the Homs suburb of al-Waer.
These actions warned opponents in Aleppo that bombardment is the price of continuing armed struggle, while aid and evacuations of fighters are granted to those who cease rebellion.
De Mistura was correct in coupling the issues of Jabhat al-Nusra and the Syrian air force action. Since last December, the US has failed to pressure the Syrian insurgent factions it supports into breaking ties and ending co-operation with Nusra, al-Qaeda' s official wing in Syria.
Although Nusra has rebranded itself as Jabhat Fatah al-Sham (Army of Conquest of Greater Syria) and formally renounced its connection with al-Qaeda, the group is still regarded as al-Qaeda’s offshoot and a “terrorist” group by the UN and the international community, including the US. Kerry has called for non-al-Qaeda factions to break with Nusra, but they have refused to cut ties.
US-backed, largely fundamentalist factions have allied with Nusra – which has 7,000 fighters, two-thirds of them Syrian – because it has the discipline and military muscle to deliver. Nusra’s participation in the August offensive against Syrian army positions in the Ramousa area southwest of Aleppo enabled insurgents to break through to besieged eastern quarters. Without air power the Syrian army would not have been able to retake the area.
Russia undertook air strikes against anti-government forces nearly a year ago at a time when the undermanned, overstretched Syrian army, bolstered by Lebanese Hizbullah and Iranian forces, had lost the northwestern Idlib province and was under severe pressure.
Air power has strengthened the Syrian army and its allies in the war on the ground, just as the pairing of Nusra with other insurgent factions has powered anti-government forces.
Kerry has seized on the bombing of the Syrian Arab Red Crescent-Red Cross-UN aid convoy last Monday night to put forward his demand for a halt to all air strikes without conceding anything on Nusra/Jabhat Fatah al-Sham, which, deemed a “terrorist” group, would not be bound by a ceasefire and, with its allies, could continue to take the fight to the Syrian army.
Following the failure to reach agreement on a ceasefire, Russian foreign minister Sergei Lavrov argued the government alone cannot be asked to take "unilateral steps" but all sides must adhere to the ceasefire. "We insist and find support for steps being taken by the opposition as well, so as not to let Jabhat al-Nusra take advantage of this situation."
Shorn of al-Nusra, groups benefiting from US support could be compelled to observe a ceasefire deal stipulating no advances on the ground for both sides. This could be a deal acceptable to the government and its partners. The US and Russia could then focus on the battle against Islamic State.
Nusra, if not pursued, could replace Islamic State if and when it is contained or defeated, making al-Qaeda the master of large areas of Syria.