Every war has certain events that open a new stage in its development and condition its evolution. In the case of Syria, it has been the rise of the Islamic State (IS) and the bombings by the US-led coalition. In all likelihood, the future will also see the Russian military intervention in Syria as a turning point.

As is well known, the Syrian conflict is much more than a civil war. Since its inception it has been distorted by the interests of other countries. Roughly speaking, there are four sides in Syria: the Assad regime, the Kurdish militias, the rebels (a swarm of militias of all ideological spectrums) and the Islamic State. In principle, the Kurds and Assad are on the same side, even if both are operating on their own and the Kurds are counting on achieving generous autonomy for their northern regions or even independence in the aftermath of the conflict. The atomized rebels are united by their hatred of Assad and their enmity towards IS, the only side that has virtually no allies.

At the international level, the Sunni countries of the Persian Gulf and Turkey directly or indirectly support the rebels (also Sunni), each one a different faction. Russia and the Shiite axis of the Middle East (basically Iran and Hezbollah) support Assad and his government controlled by the Alawite minority (identified with Shiism, although rather weakly). Finally, the US intervenes together with several Western countries directly against IS and uses some rebel and Kurdish militias to complement its strategy.

It is important to know the facts that preceded the Russian military intervention and that help explain it. First, Saudi Arabia had succeeded in forcing the coalition of several rebel groups into the so-called "Army of Conquest." The result of such coordination allowed the rebels a series of victories over the Assad regime, particularly in the northwest of the country. By August, everything seemed to indicate that the rebels' next move would be to progress southward and seize the coastal enclave of Latakia, where the Alawite minority that sustains Assad resides and where the Russian naval base at Tartus is located. Finally, rumors had grown about a possible move by the US, France and Turkey to create a refuge zone for the rebels in certain enclaves in northern Syria bordering Turkey. The establishment of such a zone would have provided the rebels with a secure base from which to reorganize and regroup in their fight against Assad and ISIS.

The surprise Russian intervention has come to put a stop to these two dangers threatening the Assad government. By bombing, Putin is trying to reverse rebel advances in Idlib and Aleppo, as well as to scare off any possibility of a joint foreign intervention in favor of the rebels. Not surprisingly, therefore, most of the Russian strikes (over 90%) have been in northwestern Syria (where there is no IS presence), which is where the Assad regime is staking its near-term future deadline. In the meantime, the Russian attacks on ISIS have been of a testimonial nature because ISIS is theoretically already taken care of by Obama and because the ISIS action area is still far from the strategic areas for the survival of the Assad regime.

Obama has insisted that the Russian intervention has not altered the campaign against ISIS, but statistics provided by the Pentagon belie such claims. Although American bombing raids in Syria were never noted for their intensity (a average of 12 per day), after Russia's entrance in the conflict they were reduced to a minimum of 2.5 strikes per day. Obama's inactivity and apathy contrast with Putin's hyperactivity, whose planes carry out more than 50 strikes a day.

At final, the Russian intervention has benefited Assad and, indirectly, ISIS, as the US has put the brakes on its already anemic campaign against the Islamic State. One wonders whether Russian support for Assad will be enough for him to prevail over the rebels. So far, in the Syrian conflict the different sides involved were too weak to win but strong enough to avoid defeat. Putin's goal is to alter this balance of forces on the ground and through an intensive bombing campaign make the rebels weak enough to lose. The only question is whether Assad will have the forces necessary to advance to victory along the path paved by Russian bombs.