The destruction of Aleppo, especially the city's eastern neighborhoods that are tenuously held by anti-regime rebels, is largely pushed out of the nightly news by the fierce fighting around the presidential race in the United States. A few doughty reporters and photographers venture into Syria, but usually the cameras stay at a safe distance, so that much of what we see are the flashes and smoke from shells and bombs bursting in its cities. At other times, we see smartphone video of haggard people running for shelter or transporting the wounded, screaming in pain, to hospitals where there is little help for them.There's a Western consensus that the Russians are assisting their Syrian allies, President Bashar Assad's forces, in pounding the city, and - with some diplomatic reservations, especially by the United Nations - that their jets destroyed an aid convoy last week. The UN Security Council last weekend heard blasts against Russia from Western powers. U.S. Ambassador Samantha Powers said that, "Instead of pursuing peace, Russia and Assad make war are bombing the humanitarian convoys, hospitals and first responders who are trying desperately to keep people alive." UK Ambassador Matthew Rycroft went further: Russia and Assad, he said, had "unleashed a new hell on Aleppo. Russia is partnering with the Syrian regime to carry out war crimes."As the Syrian ambassador was called to speak, Rycroft led a walkout of Powers and the French ambassador, Francois Delattre. Russian ambassador Vitaly Churkin then denied that Russia was involved.Why is Moscow putting itself on the wrong side of history, because who can doubt that history will record Assad as a monstrous tyrant and Russia as his sinister ally? In fact, Russia does doubt that, but it covers its reasons for the alliance with the smallest fig leaf of denial.Vladimir Putin is, bit by bit, seeking to rebuild the glory and the power that he believes was the Soviet Union. The USSR was a large player in the Middle East. Today, the sole physical inheritance from those years is the leased docking facilities at Tartus, on Syria's northern coast. After the evacuation of the Soviet bases in Egypt's Alexandria and Mersa Matruh in the late 1970s, Tartus remains Russia's only foothold on the Mediterranean. Though views differ on how vital it is - it's too small to host Moscow's larger warships - the port remains an important supply point.The Kremlin's political and strategic calculations are even more important. Putin believes that Western interventions in other countries - usually presented as humanitarian actions - mask an agenda of aggression and of neo-imperialism. In a crucial speech to the U.N. General Assembly last year, he both criticized the West for refusing to take Assad's side in the Syrian civil war and applied the same logic to Western meddling in Ukraine, where he claimed outsiders had orchestrated a military coup that "triggered civil war as a result."The Russian president sees the United States as a constant, implacable opponent, with a powerful military that must be checked at every opportunity. But there is another rationale, at once more personal and more coldly rational, for retaining the alliance with Assad. It lies in the president's experience in the Russian region of Chechnya, in the Caucasus. Chechnya's more than one million people have been among the most oppressed, and the most warlike, in both tsarist and Soviet times. The province declared independence in late 1991, as the Soviet Union was disintegrating. Russia's opposition to the nationalist uprising sparked the first Chechen war (1994-96), which left it a semi-autonomous, semi-dependent state. When war flared again in late 1999, Putin was prime minister and made most decisions in place of an ailing President Boris Yeltsin.A better prepared Russian army, fighting a war brutal on both sides, reduced much of the capital, Grozny, to rubble. By 2000, Moscow had ended most organized resistance, though guerrilla activities continued until 2007, when Ramzan Kadyrov, son of a former Chechen president and strongly backed by Putin, imposed an often corrupt and savage dictatorship. Separatism was suppressed, Grozny rebuilt and Chechnya remained loyal to Moscow.Chechnya is the model for war in Syria, Grozny the model for the assault on Aleppo. For the Russian president, all talk of truce or negotiations is so much hypocrisy, entertained only as a diplomatic cover, with no intrinsic merit. For him - as the 2015 U.N. speech made clear - this is a war fought by terrorists against a legitimate government. Once such a war starts, the only route for the government is the use of unrelenting force against its foes.The second Chechen war made a hero of then relatively unknown Putin, with his tough response to separatist attacks boosting his popularity.It was the Russian leader's introduction to a politics in which war and strength produced popularity at home - a route well-trodden in Ukraine, Crimea and now in Syria. It is ruthlessness in pursuit of power, and it makes a major player of a country much reduced in means. Aleppo is Russia's realpolitik.John Lloyd co-founded the Reuters Institute for the Study of Journalism at the University of Oxford, where he is Senior Research Fellow. The opinions expressed here are his own.