The continuation of the miseries of Syrian people is a result of two interrelated factors: The military intervention of Russia on one hand and the hesitancy of the western countries to help stop casualties in Aleppo on the other hand. Let us set the record straight, Putin is perhaps the most insensitive man on earth when it comes to human losses in Syria. He is driven by one objective: To win militarily and then claim that his country can be a counterweight to the United States. Thus far he is vindicated. The air campaign has helped prop up Assad's regime and turned the tide of war. The huge civilian toll is not something Putin is bothered about.

It is not as if the international community has no inkling of what is happening in Aleppo. In fact, the bloodbath can no longer be concealed. Moreover, Putin's belief in use of force is a well-established fact. He genuinely believes that the persistence and methodological use of force will eventually pay off. This explains the magnitude of the systematic destruction of Aleppo.

Nevertheless, it is not too late to stop the bloodbath in Aleppo. But to do that, there are two steps to be taken. First, the western countries should press for investigation into war crimes being committed by both Assad's troops and the Russian air force. The scorched earth policy Russia has been implementing for some time is yet to trigger a credible western response. Thus far, the Russian forces targeted hospitals, schools and civilians to force rebels to surrender.

Secretary of State John Kerry was right when he said, "Russia and the regime owe the world more than an explanation about why they keep hitting hospitals and medical facilities, and children and women...These are acts that beg for an appropriate investigation of war crimes." However, Kerry's statements will soon be forgotten if western countries fail to follow up on them.

Secondly, Putin will continue his war as long as his military intervention if affordable. All talks about quagmire for Russia in Syria fell on deaf ear as Putin believes that it may be an affordable quagmire. Seen in this way, the West can only play any role effectively if they match their rhetoric with deeds. It is not easy to insinuate that there is a military option. Putin understands very well that President Obama will not sanction the use of force against Assad's troops, otherwise Putin would have budged.

Putin's confidence that the "friends" of the Syrian people will not employ any force or arm the rebels with deterring weapons explains his intransigent position on Syria. Moscow even has gone a step further when it announced that it was ready to face any western offense. This kind of empty grandstanding is based on Putin's expectations that the Untied States will not attack for various reasons.

It is being said that the United States does not have the power to initiate a war-crime probe against Russia because the latter has a veto power in the Security Council. And on top of that, Russia will veto any resolution that would hold Assad accountable for the human tragedy in Syria. In the current situation everything boils down to one point: Do exactly as the Russians have been doing. Meaning, engage in a political process while simultaneously equip the rebels with anti-aircraft missiles. As long as Putin believes that he can win and that his troops run no risk, he will most likely won't take the political process seriously. Putin should understand that he cannot win a war he has waged to ensure Assad's survival and western countries should convey this message to Russia.

• Hassan Barari is a professor of international relations at Qatar University.