Smoke rises from an Aleppo building after a Russian jet carried out an air strike. Credit:Getty Images This approach could succeed even if pro-government forces never retake Aleppo. A year-long siege of the city has not brought President Bashar al-Assad's forces closer to victory. Too weak to win outright, they appear instead to be hedging, trying to weaken the rebels so that they cannot win either, and to ensure any final settlement would be more favourable for Moscow and its allies. Though killing civilians often backfires in war, in this case it may be all too effective. Aleppo is a metaphor for the larger war. The northern Syrian city is one of the few remaining strongholds for non-jihadi rebel groups. But months of siege forced them into a terrible choice: turn to extremists for help, or starve. It was no choice at all, and groups such as the jihadi-linked Ahrar al-Sham helped briefly break the siege in August. Genevieve Casagrande, an analyst with the Institute for the Study of War, said this was a victory for Russia, and likely its goal. Forcing Aleppo's rebels to co-operate with jihadis would taint them, making it harder for the West to provide them arms or include them in any peace deal.

The rubble left in Aleppo after an air strike. Credit:White Helmets/AP "Russia and the regime are driving the radicalisation of the opposition on purpose," Casagrande said. This will unify and strengthen the opposition in the short term, but in the long term will blur any distinction between jihadis and other rebels. The United States has tried to counteract this by persuading rebels to reject jihadis, in part by promising support for the opposition and by targeting jihadi militants. But the US approach has drawn the Syrian factions closer together, because rebels like those in Aleppo need urgent support on the ground and only extremist groups are available to provide it. Heavily damaged buildings after air strikes in Aleppo. Credit:White Helmets/AP The endurance of non-jihadi rebel groups poses an even greater threat to the Syrian government than the jihadis because they challenge the Syrian government's legitimacy.

That legitimacy has been weakened by years of killing civilians, and by the government's strategy of fostering sectarianism, which leaves it with little support among the country's majority Sunni population. As long as non-jihadi Sunni Arab rebels are on the battlefield, they can credibly claim to better represent Syrians. This leaves the Syrian leadership, which is dominated by the Alawite religious minority, vulnerable to any peace deal or military intervention that would install a rebel government in its place. Syrian President Bashar al-Assad. Credit:AP By forcing the rebels to unite with the jihadis, Syria's government aims to deprive the world of any acceptable alternatives for leading the country. Russia has a similar weakness. Syria, its last remaining ally in the Middle East, will remain that way only as long as it is led by the Alawite religious minority. Any democratic Syrian government would prominently feature Sunni Arabs, who are unlikely to look kindly on Russia after its role in the civil war. Moscow has probably concluded it cannot force a military victory for the Syrian government. Its year-long intervention has focused heavily on Aleppo, but pro-government ground forces are too weak to retake the divided city. Radicalising the opposition, then, can ensure that there is no viable alternative to Syria's current government.

This also accomplishes a diplomatic goal for Russia: making itself crucial for any cease-fire or peace deal. Earlier in the war, it had less sway on the international stage – and perhaps with Damascus – because it played a smaller role than other countries that had intervened. Russia was unwilling to commit ground troops, making it secondary to Iran, which had sent many. Aleppo has been an opportunity because Russian warplanes are instrumental in maintaining the siege, and because that siege has become one of the war's most terrible calamities. Russia has forced itself to the negotiating table, ensuring it will have a greater say in any outcome. That is important to Moscow for image purposes – a way to convince Russians that their government is strong and capable – as well as to ensure that any negotiated deal protects Russian interests in Syria. Still, Russia and the Syrian government could have achieved these political goals without devastating the city and its population so drastically. Why go to such extremes? The answer has to do with a fundamental imbalance between insurgent groups and foreign interventions. In any civil war, indigenous forces rely on the local population, which gives them money, food, shelter, intelligence and recruits. Rebels, including Syria's, are only as strong as their local support.

But Russia has no need for local support; its warplanes keep flying whether Syrian civilians want them there or not. The Syrian government does need popular support to survive, but it draws that from elsewhere in the country and had already functionally destroyed its support in rebel-controlled eastern Aleppo. This subverts the normal dynamics of war, such that Russia and the Syrian government stand to benefit from mass killings. The destruction of Aleppo will not persuade its residents to support the government, of course. Rather, it will inhibit their ability or willingness to help the rebels, often by forcing them to flee their homes. This weakens the rebels – not necessarily enough that pro-government forces can retake eastern Aleppo, but enough that rebels there will struggle to push beyond the city if the siege ends. This parallels Russia's conduct during its second war in Chechnya, from 1999 to 2009, when it besieged and devastated entire cities. While analysts stress that Moscow deployed very different strategies in Chechnya than in Syria, both wars reflect Russia's willingness to target civilians for military gain. All this also sends a message to Syrians outside Aleppo: Opposition groups cannot keep you safe, and siding with them puts you at risk. The goal is not to galvanise Syrians in support of the government – impossible after years of sieges and barrel bombs – but to exhaust them. These dynamics have been building for years. In early 2014, as government forces besieged rebel-held areas, threatening those communities with starvation, a Syria analyst named Aron Lund warned in a brief for the Carnegie Endowment for International Peace that rebel-held Aleppo could be next.

Loading "Imposing starvation on civilian populations is a war crime, yet like most war crimes it is also very effective," he warned. The New York Times